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Premature Infant Follow-Up

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Guidance providing follow-up care for children and adolescents born prematurely

Babies are surviving increasingly premature births due to the dramatic improvements in neonatal intensive and neurodevelopmental care techniques, including the use of prenatal steroids, surfactant, and continuous positive airway pressure (CPAP). This module focuses on the primary outpatient follow-up care of infants born at extremely low gestational ages and weights - typically ≤28 weeks and/or 1500 grams (about 3 pounds) - although much of this information also pertains to preterm infants born later in gestation.

Other Names

Premature
Preterm
Low birth weight

Key Points

Adjusted age for assessment, chronological age for immunizations
In the first 2 years, make judgments about typical or atypical findings based on the adjusted age (not the chronological age), particularly for the neurologic and developmental exams. However, administer immunizations according to chronological age.

Feeding and fortification tips

  • For premature infants with lower birth weights, continued post-discharge growth of at least 10 g/kg/d is reasonable. [Lapillonne: 2013] Slow, steady weight gain is preferred.
  • A general rule is to keep the infant on premature formula or fortified breast milk until the infant’s growth reaches the 10th percentile for uncorrected age.
  • Advance infant feedings according to the patient’s adjusted age, not their chronologic age.

Audiology follow-up
Refer all infants who stayed in the NICU 5 days or more or who have other risk factors or parental concerns by 9 months for diagnostic audiology testing, even if they passed the hearing screening in the NICU. (See Table 1, page 19 in [Joint: 2019].

Short stature
Up to 85% of infants born SGA will “catch up” by age 2. For those with short stature after 2 years of age, consider endocrinology referral for evaluation of growth and growth hormone treatment, which has been found to be efficacious and safe in children with a history of SGA. [Boguszewski: 2021] Children with Short Stature Born Small for Gestational Age provides additional information.

Clues to abnormal muscle tone
It is critical to closely monitor muscle tone and pay attention to parental reports of “early standing,” “strong legs,” or early handedness. Though these things make parents feel proud, they are red flags for increased tone. The Hammersmith Neurologic Exam (HINE) (PDF Document 254 KB) is useful for detecting atypical tone.
Connect eligible infants with a Neonatal Follow-Up Clinic
Get to know the eligibility criteria for the closest neonatal follow-up clinic and whether or not they offer traveling or telehealth services if it is not close by. Neonatal Follow-up Programs (see NW providers [0]) are appropriate and needed for all children meeting criteria, not just children with known developmental delays or complex medical conditions. Many children who appear to be developing typically have issues that can be addressed by early recognition and intervention.
Home oxygen therapy and referral to pulmonology
Home oxygen therapy is a safe and relatively convenient means for maximizing growth and development in infants with Bronchopulmonary Dysplasia. However, studies and guidelines are limited for supplemental oxygen beyond the newborn period. In general, wean oxygen in the office based on spot checks and infant growth. If the infant struggles to wean from oxygen or shows other respiratory symptoms, refer to Pediatric Pulmonology (see NW providers [0]). Some Neonatal Follow-Up Programs have a bronchopulmonary dysplasia program within them that follows patients and weans their oxygen.

Diagnosis

The initial diagnosis of prematurity and many related conditions can be found in the NICU course and discharge summary. Premature infants, particularly those born extremely early, often have or are at risk of developing bronchopulmonary dysplasia, retinopathy of prematurity, intraventricular hemorrhage, cerebral palsy, necrotizing enterocolitis, and other complications that require follow-up in the neonatal period and beyond. More details about ongoing monitoring and evaluations are in the Treatment section below.

Diagnostic Criteria & Classification

Terms describing age and birth weight are not always standard. Here is some guidance:
  • Premature (Preterm): an infant born at an estimated gestational age of less than 37 weeks
  • Early Term: between 37 weeks 0 days and 38 weeks 6 days [ACOG: 2013]
  • Late Preterm: an infant born between 34 - 36 6/7 weeks gestation. "Late preterm" replaces earlier terminology of "near term."
Gestational Age Classifications: [Eds: 2012]
  • Moderate to late preterm: 32 to <37 weeks
  • Very preterm: 28 to <32 weeks
  • Extremely preterm: <28 weeks
  • Tiny baby: < or = 23 weeks [International: 2023]
Classification by birth weight: [TeKolste: 2004]
  • Low Birth Weight (LBW): <2500 grams (5 lbs, 8 oz)
  • Very Low Birth Weight (VLBW): <1500 grams (3 lbs, 5 oz)
  • Extremely Low Birth Weight: <1000 grams (2 lbs, 3 oz)

Diagnostic Testing & Screening

Confirm what of the following were performed in the NICU and obtain additional recommended screens and tests in coordination with the outpatient medical home.

Labs

  • Newborn screening: For information about the conditions tested, see the Portal's Newborn Disorders. This varies by state but is recommended once between 1-2 days of life and again 8-21 days of life for all infants.
  • Hemoglobin/hematocrit to screen for anemia. Be aware of the timing of blood transfusions and if the infant is receiving iron supplementation. The AAP advises anemia screening for all infants at ages 9-12 months and repeated screening between the ages of 1 and 5 years for patients at risk. Early screening around 4 months of life is advised for premature infants and infants small for gestational age. (See the Bright Futures/AAP Periodicity Schedule.)

Imaging

  • Congenital heart disease screening: Pre- and post-ductal oximetry may suggest congenital heart disease; an echocardiogram would help confirm anatomy. This test is usually completed in the hospital prior to discharge.
  • Screening for developmental dysplasia of the hip (DDH): Pelvic (hip) ultrasonography screens for DDH for infants born breech, with multiple gestations or concerning findings on routine hip exam. For premature breech infants, timing of the hip ultrasound may be adjusted to 4-6 weeks for corrected post-gestational age. Screening for Developmental Hip Dysplasia—Clinical Algorithm (AAP) [Committee: 2000] provides recommendations for timing of screens and follow-up actions.
  • Head ultrasonography to screen for intraventricular hemorrhage, hydrocephalus, structural anomalies, etc. Infants born at 30 [Lahood: 2007] to 32 weeks [Sauve: 2001] gestation or earlier may benefit from routine cranial ultrasound examinations at 7 to 10 days of age and at 36 to 40 weeks postmenstrual age. [Sauve: 2001] [Nwafor-Anene: 2003]

Sensory

Hearing
Infants who did not pass an initial hearing test in the NICU should have repeat screening completed within 2-4 weeks. Follow-up testing for high-risk premature infants is recommended at 9 months, 2 years, and 4 years (adjusted ages). [Journal: 2019] Refer sooner if there are language or hearing concerns. Premature infants are considered high risk if there is a history of any of the following:

  • Hypoxic-ischemic encephalopathy (HIE)
  • Extracorporeal membrane oxygenation (ECMO) use
  • Meningitis
  • Congenital cytomegalovirus (CMV)
  • Hyperbilirubinemia (specifically for infants with a history of total serum bilirubin >=20, a brainstem auditory evoked response (BAER) test is recommended within 3 months of birth) [Phillips: 2013]
  • Craniofacial abnormalities
  • Family history of childhood hearing loss
  • Parental concerns
  • Chronic otitis media

States that meet the 1-3-6 benchmark should strive to meet a 1-3-6 month timeline. Goals include:

  • All infants should undergo hearing screening prior to discharge from the birth hospital and no later than one month of age, using physiologic measures with objective determination of outcome.
  • All infants whose initial birth screen and any subsequent rescreening warrant additional testing should have appropriate audiologic evaluation to confirm the infant's hearing status no later than 3 months of age.
  • A concurrent or immediate comprehensive otologic evaluation should occur for infants who are confirmed to be deaf or hard of hearing.
  • All infants who are deaf or hard of hearing in one or both ears should be referred immediately to early intervention in order to receive targeted and appropriate services by 6 months.

For more information on how hearing is tested and normal milestones for hearing and language, see Hearing Screening.

Vision

  • Infants less than 30 weeks get ROP screening in the hospital by 32 weeks postmenstrual age or 5 weeks postnatal age, whichever comes last. Follow-up assessments for retinopathy of prematurity (ROP) are based on initial findings. See Premature Infant and Retinopathy of Prematurity for information about risk factors and treatment considerations.
  • For premature infants who were not identified with ROP, routine well-child checks should include an eye exam that screens for strabismus, difficulty with visual fixation/following and acuity, and atypical eye movements.
  • All infants born weighing 1500 grams or less, as well as those affected by intraventricular hemorrhage (IVH), should be considered for ophthalmology referral within 4 to 6 months after discharge. Even in infants whose ROP exams reveal the resolution of ROP, follow-up with ophthalmology is recommended due to the high prevalence of problems of visual acuity and strabismus in this population.

Other Screening & Testing

Car seat testing
Oximetric evaluation of ability to safely transport in car seat vs. car bed should be performed prior to hospital discharge for infants born <37 weeks gestation. It may need to be repeated in the outpatient clinic to wean an infant discharged on oxygen for use in the car. Guidelines include:

  • Oxygen saturation not falling <90% for >10 seconds or heart rate < 80 bpm for >10 seconds on room air for at least 90 minutes or the duration of the car ride (whichever is longer).

Developmental screening
According to the AAP's recommended schedule for Developmental Screening, the primary care clinician should perform developmental screening at the child's adjusted age rather than chronologic age until 30 months (or 24 months if there will be no 30-month evaluation). Children enrolled in Neonatal Follow-Up Programs will undergo formal developmental testing through the program.

Consider Autism Screening and screening for disorders of hyperactivity and the ability to focus. (Infant & Early Childhood Social-Emotional Screening and Developmental Screening have links to screens and guidance for responding to a positive screen.

Testing for Family Members

Postpartum depression is 3 times more likely to occur in mothers of preterm infants than in mothers of full-term infants. [Phillips: 2013] Examples of Standardized Screening Tools are:

Given the peak times for postpartum depression, screening should be integrated at the 1-, 2-, 4-, and 6-month visits. [Earls: 2019] Management of positive screens and additional information can be found at Postpartum Depression Screening.

Genetics

Women who have had 1 infant born prematurely are at higher risk for a second premature infant. This risk increases with decreasing gestational age of the first premature child. While the overall rate of prematurity is 8.76 % in the United States, the rate for African-American women is 12.18%. [Osterman: 2023] This risk factor is found in studies that have controlled for economic status, maternal education, and coexistence of other maternal medical risk factors. Additionally, women born prematurely are more likely to deliver their infant prematurely.
A maternal history, including medication and substance use, history of prior pregnancy complications, and chronic medical conditions, helps determine the risk of having another premature infant. If subsequent children are desired, referral to appropriate obstetric experts (maternal-fetal medicine) will help the mother plan for a safe delivery. Mothers born prematurely are also at increased risk of giving birth prematurely. [Institute: 2007] Premature birth prevention programs may be available in certain areas. See Prevention of Recurrent Preterm Birth.
At the time of writing this article, no identified genetic mutations lead directly to prematurity. What is known is that maternal genetics do play a role, but fetal and paternal genetics do not. Large sample sizes are needed to further evaluate this. [Wadon: 2020]

Incidence & Prevalence

The preterm birth rate (<37 weeks) in the United States in 2021 was 8.76%, and the rate of infants born at <34 weeks was 2.81%. <1% of infants are born before 27 weeks. [National: 2020] [Osterman: 2023]

Comorbid Conditions

The NICU discharge summary and the caregivers' stories are the primary sources of medical diagnoses that require follow-up care. The following items warrant special attention in primary care follow-up:
  • Cardiac and/or respiratory arrest
  • Complex congenital heart disease
  • Heart murmur that is still present at discharge and cause, if known
  • Necrotizing enterocolitis (NEC) with perforation
  • Bronchopulmonary dysplasia / Chronic lung disease of prematurity
  • Pulmonary hypertension
  • Prolonged period on ventilator for respiratory failure (beyond the time of initial stabilization of the transitioning infant)
  • Chronic hypoxemia and discharged on home supplemental oxygen
  • Evaluation for and, if present, the degree of retinopathy of prematurity
  • Failed hearing screens and follow-up instructions
  • Intraventricular hemorrhage grade. (While all level bleeds I-IV represent an adverse event in the brain, grades III and IV are associated with a significantly increased risk for neurodevelopmental impairment.)
  • Periventricular leukomalacia
  • Hydrocephalus
  • Evidence of cerebellar injury
  • Neonatal seizures
  • Cerebral Palsy
  • Current feeding plan, dietary supplements, and need for feeding therapy and/or tube feedings
  • Surgical scars
  • Breech delivery
As follow-up continues, additional comorbid conditions may arise even if not evident during the neonatal period, including:
  • Developmental delays
  • Sensory disorders (hearing or vision)
  • Neurobehavioral difficulties
  • Neurological disorders, including cerebral palsy, attention deficits, and seizures
  • Head shape deformities
  • Hip dysplasia
  • Cardiovascular disorders, including patent ductus arteriosus and persistent pulmonary hypertension
  • Hypertension
  • Respiratory disorders, including bronchopulmonary dysplasia (aka chronic lung disease of prematurity), prematurity-related respiratory disease, sleep-disordered breathing (obstructive and/or central sleep apnea), and chronic hypoxemia
  • Gastrointestinal disorders, including dysphagia, reflux, and surgically related bowel disorders
  • Anemia: Be aware of the timing of prior blood transfusions and if the infant receives iron supplementation through formula and/or supplements. Hemoglobin/hematocrit is often used to screen for anemia; however, testing reticulocyte hemoglobin, iron studies, reticulocyte counts, or ferritin will increase sensitivity.
  • Endocrine disorders, including hypoglycemia and cortisol deficiency
  • Urological problems, such as undescended testes, hernias, or stones
  • Infections such as RSV that can lead to increased risk of subsequent hospitalization

Prognosis

Prematurity is the second leading cause of infant mortality in the US, behind congenital malformations. [Mathews: 2017] The infant mortality rate declined from 2005 to 2014, according to data from the National Child Health Survey, from 113.5 to 104.6/1000 live births. The greatest contribution to this decline (69%) can be attributed to improvements for infants born <32 weeks, and this was true for the entire population and for each race and ethnicity. Another 31% of the decline in infant mortality is due to improvements in the gestational age distribution. [Callaghan: 2017] Survival and outcomes for children born very prematurely have improved dramatically over the past 4 decades. Yet, associated morbidities can occur following delivery or may unfold as chronic disabilities, such as cerebral palsy, cognitive impairment, vision and hearing impairment, feeding disorders, cardiac or respiratory conditions, and/or behavioral disabilities. In a multi-centered, longitudinal study of children born less than 29 weeks gestation, the overall survival rate has increased from 2012 to 2018. Of those who were evaluated at 22-26 months of age, adjusted, 48.7% had no or mild neurodevelopmental impairment, 29.3% had moderate neurodevelopmental impairment, and 21.2% had severe neurodevelopmental impairment. 8.4% had moderate to severe CP (GMFCS level III- V), 1.5% had bilateral blindness, 2.5% required bilateral hearing aids or had cochlear implants, and 49.9% had been rehospitalized. [Bell: 2022]

Primary care clinicians have unique opportunities to prevent or limit secondary disabilities in preterm infants. [Novak: 2017] Primary care physicians have an important role in detecting early risk factors for cerebral palsy, beginning with knowledge of the initial history and NICU course. Prompt referral to diagnostic-specific early intervention to optimize infant motor and cognitive plasticity, prevent secondary complications, and enhance caregiver well-being is essential. [Novak: 2017] Using tools with the highest evidence, the age of diagnosis of CP can be decreased from 12-24 months to a corrected age of 6 months or earlier. [Byrne: 2017]

Treatment & Management

Often, during prolonged NICU hospitalizations, families become attached to and dependent upon the NICU staff, making the transition to primary care difficult. To help with the transition, the medical home clinician would ideally communicate with parents and the NICU staff or visit the infant before NICU discharge. The primary care team/medical home often needs to manage supplemental oxygen, feedings through gastrostomy or jejunostomy tubes, specialized immunizations, specialized formulas, and care coordination with multiple subspecialists and/or developmental therapists. Ideally, the NICU discharge summary would indicate needed subspecialty follow-up (e.g., cardiology, pulmonology, ophthalmology). Ongoing medical home care includes coordination of care specialists, studies, and programs such as a Neonatal Follow-Up Clinic to avoid service duplications.

The initial follow-up visit is optimal within 1 to 2 days of leaving the hospital and enables the primary care clinician to:

  • Establish a baseline weight, which helps guide feeding adjustments over time.
  • Provide additional training and reassurance about infant care outside of the hospital setting.
  • Educate families about additional medications and supplies that may be needed at home.
  • Update vaccinations as needed (family members can also be encouraged to obtain vaccines). Guidance on immunizing former premature infants can be found in a Clinical Report from the American Academy of Pediatrics' Committee on Infectious Diseases. [Saari: 2003] In general, vaccinations should be given based on the child's actual age and not their corrected age.

Nutrition/Growth

Advancing nutrition
Premature infants' nutritional needs and feedings are not the same as those for full-term infants; they often require concerted effort to manage them effectively in the medical home. Feeding difficulties or gastrointestinal complications such as developing oral motor dysfunction and oral aversion, gastroesophageal reflux, and dysmotility can affect the preterm infant's nutrition. Despite the NICU feeding summary, unanticipated changes may occur after discharge, or the infant may no longer tolerate the schedule or the formula used in the NICU. Therefore, monitoring the infant's growth rates, feeding volumes and skills, and adjusting nutrition are important roles of the medical home team. Consideration of the caregiver's skills and understanding is key with regard to feeding and should be assessed and monitored. Adaptations may have to be made to the NICU discharge feeding plans. Specialists in lactation, nutrition, or gastroenterology can be helpful resources. Preterm infants have increased demands for protein, calcium, and energy. For information about energy/protein/vitamin needs of the premature infant, human milk fortifier use, and specialized preterm formula components, see the Portal's issue page about the Nutritional Needs of the Preterm Infant.
  • Advance infant feedings according to the patient's adjusted age, not their chronologic age.
  • A general rule is to keep the infant on premature formula or fortified breast milk until the infant's growth reaches the 10th percentile for uncorrected age. Diluting the premature infant 22 kcal/oz formula to 20 kcal/oz can continue to provide higher protein in premature infants who gain weight rapidly but could still benefit from added protein to support their linear growth. Frequent monitoring of the infant's growth rates, feeding volumes and skills, and adjusting nutrition accordingly, are important roles of the medical home team.
Bone health
Infants should get at least 400 IU of Vitamin D daily. If infants experience complications that interfere with adequate nutrition, osteopenia may result, and fractures could occur. See Osteoporosis and Pathologic Fractures.
Provide a 400 IU dose daily for infants who are fed breastmilk exclusively. For infants who drink formula in addition to breastmilk or as the sole source of nutrition, supplement vitamin D if the infant takes less than the following per day:
Similac:
  • 33 oz of 20 kcal/oz formula
  • 30 oz of 22 kcal/oz
Neosure:
  • 26 oz of 22 kcal/oz formula
  • 24 oz of 24 kcal/oz
Growth: Measurements and goals
  • Plot measurements for preterm infants weighing 1500 grams or more by chronological age on a standardized growth chart for term infants, and then correct back for adjusted age. This can be continued until the child reaches 2 years of age when plotting solely by chronological age becomes appropriate. If available, the Fenton growth chart can be used as well.
  • For premature infants with lower birth weights, continued post-discharge growth of at least 10 g/kg/d is reasonable. [Lapillonne: 2013] For infants with IUGR, a slow, steady weight gain is preferred as rapid weight gain can be related to adult chronic disease and obesity.
  • Skin-fold measurements can help identify older children who may be "overfat" despite "normal weight" due to low muscle mass and bone density, such as in non-ambulatory children. See Premature Infant Growth Charts.
For formerly premature infants with short stature who do not catch up with linear growth by 2 years of age, consider endocrinology referral for evaluation of growth and growth hormone treatment, which has been found to be efficacious and safe in children with a history of SGA. Children with Short Stature Born Small for Gestational Age provides additional information.
Iron supplements
There is a lack of consensus about iron supplementation. Consideration must be given to the use of iron-containing formulas, fortifiers, multivitamins with added iron, and foods, as well as the history of erythrocyte transfusions, as premature infants may also develop iron overload. Iron supplementation can cause gastric upset and hard or darkened stools.
Recommended iron supplementation on the lower end for routine care of late preterm infants is 2-4 mg/kg/day. Common formulations for babies contain 15 mg of elemental iron per 1 mL of liquid.
Start iron supplementation around 4 weeks of life and continue until approximately 12 months of age, or when the child can ingest adequate iron from food or formula.
Lab monitoring can determine if iron supplements continue to be indicated, especially if the infant is suspected of having GI side effects from added iron.
Feeding tubes
Motility problems, feeding difficulties, reflux, and/or aspiration may contribute to the need for gastric or jejunal feeding tubes. If such a device is in use, the family and primary care provider need to understand how the device works and how to access information should it stop working or need to be replaced. The primary care clinician should review this care plan with the family. See the Portal's page about Feeding Tubes & Gastrostomies in Children for further information.
Oral aversion
Oral aversion in the preterm infant may result from a complex interplay of both medical and behavioral factors. Oral aversions may be short-lived or can go on for years. When an oral aversion occurs, it is important to get specialists involved as soon as possible to begin teasing out the reasons for the problem and begin therapeutic intervention. This can be as important for the parent as for the child. Speech and language pathologists, occupational therapists, and psychologists with experience in infant feeding difficulties can be very helpful and supportive to families. Often, Early Intervention specialists also have a special interest in and experience with these difficulties.

Gastro-Intestinal & Bowel Function

Gastroesophageal reflux (GER)
Premature infants may have difficulties with GER due to the immaturity of, and insult to, the gastrointestinal tract. In most babies, GER is a benign occurrence that does not cause pain or impair feeding or growth. It peaks around 4 months of age and gradually diminishes over the first year. Sometimes, though, it can cause severe pain and poor growth. Symptoms of GERD include feeding refusal, recurrent vomiting, poor weight gain, irritability, sleep disturbances, and respiratory symptoms such as coughing, wheezing, or recurrent pneumonia. GER is usually managed with avoidance of overfeeding, positioning, removal of dairy from the diet, or thickening of formula. [Lightdale: 2013] Thickening of breast milk is usually not recommended because the live enzymes in breast milk start to digest the thickeners and can make the breast milk thinner. Caution should be used when prescribing medications for reflux as there is limited data on safety and efficacy. [D'Agostino: 2016] The Portal's page about Gastroesophageal Reflux Disease provides the details of these treatments.
Cholestasis
For those preterm infants with cholestasis (decreased bile flow) either from total parenteral nutrition (TPN) in the NICU or from other underlying medical causes, it is important to monitor laboratory values, such as direct and indirect bilirubin, CMP, GGT, PT/INR, and PTT, and closely monitor the infant's growth. Cholestasis can result in pruritus (itching), steatorrhea (fatty stools), and growth difficulties; additional caloric supplementation may be required. Medium-chain triglyceride oil, additional protein, and fat-soluble vitamins may be needed; supportive medications, such as ursodiol, may need to be weaned as an outpatient in consultation with a liver/gastroenterology specialist. The most important diagnosis to consider is biliary atresia, as earlier treatment leads to better outcomes. Most infants will need evaluation with a liver specialist. [Fischler: 2014]
Oral motor dysfunction
Preterm infants who experience prolonged endotracheal intubation and/or illness may miss coordinated suck and swallow stages of their development. Neurologic impairments, such as hydrocephalus or intraventricular hemorrhage, can contribute to oral motor dysfunction, leading to oral pharyngeal dysphagia, resulting in aspiration of fluid into the lungs and possible oral aversion. A video swallow study can help determine abnormalities in the child's swallowing mechanism and provide guidance for intervention. Depending on the severity, a variety of thickeners may be recommended, or a gastrostomy tube may be necessary for hydration and nutrition. Continued non-nutritive oral motor stimulation through active therapy is critical to maintaining and developing coordination of suck and swallow.
Gastrointestinal dysmotility and gastroparesis
Gastrointestinal dysmotility in preterm infants is often characterized by distention, vomiting, constipation, or diarrhea and may be caused by delayed introduction of enteral nutrition or immaturity of the GI system. The risk for gastrointestinal dysmotility is also higher in preterm infants due to the increased prevalence of necrotizing enterocolitis (NEC), with around 5% developing stage 2 or higher NEC and 20-40% requiring surgical intervention involving removal of portions of the intestines. The cause of NEC remains unknown despite years of study. [Yee: 2012] Promotility agents like erythromycin have been used as a rescue medication for premature infants with gastrointestinal dysmotility. However, due to safety concerns such as cardiac arrhythmias, their use is undergoing continual reassessment and scrutiny. Therefore, it may be necessary to seek guidance from a pediatric gastroenterologist. [Shakir: 2018] Use of probiotics in preterm infants may reduce the risk of NEC in observational studies. [Olsen: 2016]
Umbilical hernias and diastasis recti
Umbilical hernias, caused by incomplete closure of the abdominal muscles around the site where the umbilical cord was present in utero, occur more frequently in premature infants. When a loop of intestine protrudes into this area, it can stick out. Crying and bearing down can make these hernias more noticeable.
  • If the hernia remains reducible, surgery is not required. Typically, umbilical hernias self-resolve over the first few years of life.
  • Diastasis recti (incomplete closure of the abdominal wall muscles) usually resolves in the first couple months of life. This benign condition does not require surgical intervention.

Respiratory

Respiratory rate generally follows corrected gestational age norms. [Trachtenbarg: 1998]

Apnea of prematurity and SIDS risk

Preterm infants exhibit various breathing patterns, including normal breathing, periodic breathing (which involves short pauses followed by rapid breathing), and more concerning hypoventilatory and apneic episodes. Apnea is defined as no breathing for at least 20 seconds or a shorter pause associated with bradycardia and color changes such as pallor or cyanosis. These episodes are often mixed central and obstructive apnea and can be worsened by infections and metabolic conditions. It is necessary for infants to demonstrate several days of no apnea before leaving the NICU. Although premature infants are at a higher risk of Sudden Infant Death Syndrome (SIDS), apnea of prematurity is not directly linked to SIDS. Peak incidence of SIDS in extreme preterm infants starts at 40 weeks post-conception age, while in term infants, it starts at 44 weeks post-conception age and lasts for 3-4 months. Monitoring may be discontinued safely by 43-44 weeks post-conception age. [Bright: 2017]

Chronic hypoxemia and oxygen monitoring
Infants may be discharged on supplemental oxygen for chronic, stable hypoxemia. For infants whose eyes have not fully vascularized, oxygen saturation may be maintained in a lower range as recommended by their NICU team or ophthalmologist. [Hayes: 2019]
  • Oxygen saturation should be measured in clinic for premature infants requiring supplemental oxygen, noting whether supplemental oxygen was used during the oximetry.
  • Assess respiratory rate and work of breathing, including subcostal and supraclavicular retractions, head bobbing, or nasal flaring. Listen for crackles, rhonchi, wheezing, or stridor.
  • For families monitoring at home, inquire about desaturations, apneas, and bradycardia frequency, duration, and interventions.
Knowing when to wean home oxygen can be difficult as the short evaluation in the office may not show the full picture. For infants greater than 37 weeks PMA, saturations >93% are preferred for optimal growth and lung development. Infants may have lower oxygenation in sleep and may need oxygen only at night time and naps. Referral to a pulmonologist may be helpful if the infant is having trouble weaning their oxygen support, is growing poorly, or is having other unexplained respiratory symptoms like wheezing, tachypnea, or retractions.
Respiratory disease
Monitor for respiratory disease related to prematurity, such as symptoms of shortness of breath with activities or hypoxemia with viral infections. In addition to routine vaccines, infants and children with BPD should be considered for immunization with palivizumab (Synagis) and 23-valent pneumococcal (Pneumovax-23 or PPSV23). [Pickering: 2012]
Bronchopulmonary dysplasia (BPD)
Bronchopulmonary dysplasia (BPD) is a form of chronic lung disease that primarily affects children born very preterm. The diagnostic criteria for BPD have changed over the years, and the best definition is still controversial.
A preterm infant (<32 weeks gestational age) with BPD has persistent parenchymal lung disease confirmed by radiography, and at 36 weeks, PMA requires 1 of the following interventions.
  • Grade 1 BPD includes infants who require nasal cannula flow of <2 L/min regardless of FiO2.
  • Grade 2 BPD includes infants who require nasal cannula flow of >2 L/min or noninvasive respiratory support (nCPAP or NIPPV) regardless of FiO2.
  • Grade 3 BPD includes infants who require invasive PPV. [Higgins: 2018]
See Bronchopulmonary Dysplasia for management information.
Vocal cord paralysis
Paralysis of the vocal cords may be unilateral or bilateral, and they can be secondary to anatomical problems or due to trauma during surgery or intubation procedures. In unilateral vocal cord paralysis, a weak cry is often noted, as well as stridor when stressed. Unilateral paralysis often resolves within the first year; however, infants with vocal fold immobility due to PDA closure are more likely to have persistent paralysis. Bilateral paralysis has more severe symptoms and may require tracheostomy. When caring for infants with vocal cord paralysis, the clinician must be vigilant for aspiration. A pediatric ENT specialist should follow children with vocal cord paralysis. [Jabbour: 2017]
Laryngomalacia
Relatively common, this congenitally flaccid larynx can result in upper airway noises, including stridor, a coarse inspiratory noise that may develop typically within a month after birth. The intermittent airway obstruction is worse with agitation and crying, tends to progress during the first 8-12 months, then resolves by age 2. Positioning and calming are conservative management tools; very severe cases may require corrective surgery (supraglottoplasty) or tracheostomy. Control of gastroesophageal reflux and minimizing aspiration may be valuable. [Jabbour: 2017]
Tracheomalacia
Tracheomalacia occurs when there is weakness of the cartilages that support the trachea, either related to incomplete development or to trauma from prolonged intubation, GERD, or abnormal surrounding structures. Tracheomalacia may arise during the first year of life and is associated with abnormal breathing, such as wheezing or stridor, dyspnea or apnea, or recurrent respiratory infections. Children with congenital abnormalities such as Trisomy 21, congenital heart disease, or tracheoesophageal fistula have higher rates of tracheomalacia or bronchomalacia. An ENT specialist or pulmonologist can diagnose tracheomalacia with endoscopy. Interventions may include supportive care, treatment of reflux, CPAP, and/or surgery. Most cases of tracheomalacia resolve spontaneously by age 2. [Fraga: 2016]
Aspiration
Preterm infants have a higher risk of aspiration, which can present with choking, coughing, and cyanotic spells associated with feeds. Recurring pneumonitis or pneumonia may also indicate aspiration. A modified barium swallow study, accompanied by an evaluation from a feeding therapist, can provide valuable information for safe feeding practices. Feeding adaptations may include thickened liquids or tube feedings for infants with aspiration.

Cardiovascular

Premature infants are at risk for a variety of conditions, including congenital heart disease, persistent pulmonary hypertension, patent ductus arteriosus, hypertension, and thromboembolism. Not all of these will be diagnosed during the NICU stay. For outpatient follow-up visits, assess rate, rhythm, pulses, and blood pressure routinely.
  • Use chronological age norms for heart rate. [Trachtenbarg: 1998]
  • Use blood pressure charts with age-appropriate norms; daily home blood pressure monitoring can also help with babies discharged on antihypertensive medication. [Flynn: 2016] Prognosis is usually good.
  • Note the grade (1-6) of any murmurs. Implementation of universal screening for congenital heart disease is helping identify some but not all cardiovascular lesions. The most common heart murmurs heard in premature infants include the patent ductus arteriosus and physiologic peripheral pulmonary stenosis. Murmurs often come and go within the first 18 months of life and often are benign. Seek further evaluation in murmurs that sound ominous, worsen over time, or are associated with feeding difficulties, respiratory distress, poor growth, sweating while feeding, tachycardia, and tachypnea. Demonstrations: Heart Sounds & Murmurs (University of Washington) has audio demonstrations of various murmurs.
Patent ductus arteriosus (PDA)
The ductus arteriosus, an essential structure for fetal circulation, typically closes spontaneously after birth within the first day of life. A PDA in full-term infants usually is monitored until spontaneous closure occurs; however, surgery may be recommended if not closed by 6 months of age. PDA occurs more frequently in premature and small babies; 30% of infants weighing <1.5 kg at birth have a PDA. While spontaneous closure may occur in preterm infants, a PDA resulting in congestive heart failure and respiratory distress may require therapy to close the ductus. There are both medical and surgical options, including ductal ligation, and these are typically managed in the hospital setting. In recent years, more infants are getting conservative management of their PDA, and so outpatient providers will encounter more infants with an untreated PDA. A pediatric cardiologist can help monitor these infants and determine if closure is needed. [Hamrick: 2020]
Ventricular septal defect (VSD)
Infants with VSD (a persistent opening between the right and left ventricles of the heart) often are asymptomatic, and spontaneous closure frequently occurs. The murmur may be appreciated clinically as a holosystolic or pansystolic murmur; however, large defects may not create an audible murmur. An electrocardiogram and chest radiograph can be reassuring, but an echocardiogram is diagnostic. Large defects that do not spontaneously close can lead to congestive heart failure and other complications. Consultation with a pediatric cardiologist is helpful for family reassurance and to manage symptomatic defects.
Atrial septal defect (ASD)
Typically, this is an incidental finding and may resolve in the first year. ASDs infrequently require surgical intervention. Consult a pediatric cardiologist if a known ASD is associated with feeding difficulties, respiratory distress, poor growth, sweating while feeding, tachycardia, and tachypnea.
Persistent pulmonary hypertension of the newborn (PPHN)
When pulmonary vessels do not relax sufficiently to effectively adapt to the extrauterine environment, the high pulmonary vascular resistance can lead to pulmonary hypertension and right ventricular dilation and/or hypertrophy. In response, the heart may shunt blood across the ductus arteriosus and the foramen ovale, which may lead to hypoxemia. Treatments are focused on improving any underlying lung disease as well as reducing or eliminating pulmonary hypertension. Interventions may include supplemental oxygen (which acts as a pulmonary vasodilator), surfactant, mechanical ventilation, inhaled nitric oxide, ECMO, correction of metabolic abnormalities, thermoregulation, and anti-pulmonary hypertensive medications. This condition tends to happen more frequently in near-term or term infants. These infants are at increased risk of adverse neurodevelopmental outcomes and sensorineural hearing loss; therefore, these conditions should be monitored in the outpatient setting. [Tauber: 2019] For infants on supplemental home oxygen for PPHN, consult the pediatric cardiologist before weaning support.
Hypertension
Preterm infants are at increased risk of hypertension. Approximately 2% of NICU graduates have hypertension, defined as >95th percentile for the infant’s size, gestational age, and postnatal age [Nickavar: 2014], often from renovascular issues. This risk increases if the infant has undergone umbilical artery catheterization, has received extracorporeal membrane oxygenation (ECMO), or has comorbid conditions such as renal, endocrine, cardiac, or pulmonary problems (including bronchopulmonary dysplasia), or has a history of intraventricular hemorrhage (IVH). Consult a pediatric nephrologist and/or cardiovascular specialist for suspected hypertension, as management may require fluid restriction, dietary changes, or medications.
Thromboembolism
Premature infants often undergo invasive catheterization at birth or during the NICU stay. Invasive catheterization of arteries and veins increases the risk of thromboembolism, such as in the aorta or renal blood vessels. When the renal vessels are affected, the infant may develop hypertension, impaired urine excretion and kidney function, congestive heart failure, and impaired blood flow to the lower extremities. Babies may require intervention for thrombolysis and medications to control blood pressure. Thrombosed kidneys may atrophy over time, leading to sustained renal insufficiency and hypertension. Ongoing management may include monitoring blood pressure and kidney function with serum creatinine clearance and urine studies, and ultrasonography.

Neurology

Infants born preterm are at an increased risk for neurological damage, which can lead to cerebral palsy, including tone abnormalities, motor delays, and other neurodevelopmental problems. At particular risk are those infants with a history of intraventricular hemorrhage (IVH), post-hemorrhagic hydrocephalus, neonatal seizure(s), neonatal stroke, periventricular leukomalacia (PVL), cerebellar injury, and porencephaly. Infants with brain injury either from before or during birth, or after complications of their neonatal care, may also develop seizures. The basic neurologic exam, including cranial nerves, muscle strength, tone, and deep tendon reflexes, should be performed routinely and documented to allow ready tracking of progress. Motor delays, before 1 year adjusted, are not uncommon and warrant further evaluation. [Wilson: 2004] [D'Agostino: 2010] Refer infants with prematurity or concerns of developmental delays to Early Intervention services for targeted therapies (Early Intervention for Children with Disabilities/Delays (see NW providers [3]).

Specialized preterm infant follow-up clinics are becoming more available and can help detect and address complications. International guidelines emphasize the importance of early diagnosis so that targeted early interventions can begin. [Novak: 2017] The goal is to maximize the outcomes for babies at high risk for motor impairment and cerebral palsy (10-15% of infants born ≤26 weeks develop CP). [Ferré: 2016]
Cerebral palsy (CP)
CP occurs in approximately 12-15% of extremely premature infants. Although the injury is not progressive, it may take time, serial examinations for developmental delays, and recognition of abnormal movement patterns to recognize CP. Early identification and initiation of intervention are essential to the optimal outcome of the child.
Tools for identification may be used in the NICU, such as the General Movements Assessment (GMA). Further evaluation by the Neonatal Follow-up Clinic may include a specific neurologic exam, the Hammersmith Neurologic Exam (HINE) (PDF Document 254 KB), a 5-10 minute exam that evaluates for tone, posture, cranial nerve findings, reflexes, and movements. The Early Detection/Early Identification/Early Intervention initiative (Cerebral Palsy Foundation) includes training providers to perform the HINE so it can be used to identify those children at risk for CP and enroll them in targeted early intervention services to maximize their outcomes.
Therapy for motor abnormalities can and should be initiated within the NICU and at discharge. Waiting for a diagnosis unnecessarily delays therapeutic intervention. Many rehabilitative services are available to help children with CP and their families. Please see the Cerebral Palsy for evaluation, management, and services information.
Seizures
Seizures may occur at any age. Neonatal seizures are those with onset between 0-2 months. Infantile spasms are a severe type of early seizure and are often related to perinatal asphyxia, prenatal infections, or other conditions such as tuberous sclerosis or metabolic disorders. Some seizure types do not require antiepileptic medication, but they do require special precautions during bathing and other activities. The Portal modules Seizures/Epilepsy and Infantile Spasms contain diagnosis and management details.

Hematology/Oncology

Premature infants suffer from a variety of hematologic problems, though most of these are discovered and managed in the NICU. The outpatient pediatrician should ensure that the newborn screen is completed according to state guidelines to assess for hemoglobinopathies and screen for anemia per AAP guidelines.
Anemia
Premature infants are at a higher risk of anemia due to a lack of iron from the placenta in the final weeks of pregnancy. The outpatient pediatrician should be aware of the timing of prior blood transfusions and if the infant receives iron supplementation through formula and/or supplements. Hemoglobin/hematocrit is often used to screen for anemia; however, testing reticulocyte hemoglobin, iron studies, reticulocyte counts, or ferritin will increase sensitivity. The AAP Bright Futures recommends screening premature infants for anemia at 4 months of age, and universal anemia screening is advised at 12 months for all babies (see Bright Futures/AAP Periodicity Schedule) .
Hyperbilirubinemia
Premature infants are at higher risk of elevated bilirubin due to delayed feeding or other medical problems. They are also at a higher risk of neurotoxicity at lower bilirubin levels. Most infants will have their hyperbilirubinemia treated in the hospital prior to discharge. However, some may need continued home phototherapy afterwards. Infants on home phototherapy should have their bilirubin checked daily to determine when to stop treatment. Additionally, infants who struggle with elevated total bilirubin for more than 1-2 weeks should have a direct bilirubin checked to evaluate for cholestasis.

Urology

Monitor for urological problems in premature infants, including inguinal hernias and kidney stones in males and females and undescended testes and hydroceles in males. Cryptorchidism is more common in premature versus term infants but also has a higher rate of spontaneous descent (80-90%) within the first year of life.
Nephrocalcinosis/kidney stones
Calcium deposits in the renal interstitium, known as nephrocalcinosis, occur in many premature infants. There is an increased risk for infants who receive loop diuretics, such as for chronic heart or lung disease, which can cause hypercalciuria. While these kidney stones typically resolve within the first few months after discontinuing diuretics, there is concern that persistent stones may inhibit kidney development and impair function. Ultrasonography is useful for identifying stones, and measurement of spot urine calcium and creatinine ratio can help to monitor for adequate excretion.
Inguinal hernias
Inguinal hernias occur in 11% of infants born under 1500 grams and are more commonly found on the right side and in male infants. [Kumar: 2002] During fetal development, testicles pass from the abdomen into the scrotum through the inguinal canal. If there is incomplete closure of this canal after birth, an inguinal hernia may occur. This can allow a loop of intestine to sag through the inguinal canal and into the scrotum, which presents risks for strangulated bowel. Since girls have inguinal canals, they are also at some risk for hernias. Refer inguinal hernias for surgical repair. [McInerny: 2008]
Hydrocele
Premature and low birth-weight infants are at risk of developing unilateral or bilateral hydroceles, or excess fluid in the scrotum, due to incomplete closure of the processus vaginalis. These typically transilluminate and often resolve spontaneously, but some will require surgery to close. Refer communicating hydroceles upon discovery to prevent incarceration; refer other hydroceles if problematic and not resolved by 1 year. [McInerny: 2008]
Undescended testes
In premature males, undescended testes are common. If not self-resolving in the first 6 months, or if worsening, a surgical referral should be made.
Circumcision
Male infants born prematurely may not be offered a circumcision procedure in the NICU. Information can be provided to interested families about safely obtaining circumcision based on their child's age, size, and health. In the author's practice, it is common to offer circumcisions based on adjusted age rather than chronological age, although this depends on the comfort of the outpatient provider. Some families may elect to have a circumcision performed if the child is undergoing sedation for another procedure. Refer families interested in circumcision to a pediatric urologist if there are anatomical concerns or the infant is beyond the age and size of what can be performed in the outpatient primary care setting. Providers should ensure that infants undergoing circumcision receive a vitamin K intramuscular shot at some point prior to the procedure to reduce the risk of catastrophic bleeding.

Immunology/Infectious Disease

Identify premature infants who qualify for special immunizations such as palivizumab (Synagis) and pneumococcal polysaccharide vaccine (PPSV23). The AAP recommends palivizumab treatment for:
  • Infants born before 29 weeks gestation who are younger than 12 months at the start of the RSV season. Infants born during RSV season may require less than 5 doses.
  • Infants born before 32 weeks gestation who have chronic lung disease defined as requiring >21% oxygen for at least the first 28 days of life. (This definition may be changing; see BPD above). Consider treatment during the second year of life in these infants if they still require medical support for their lungs in the 6 months prior to the second RSV season.
  • All infants with hemodynamically significant congenital heart disease born less than 12 months prior to the start of RSV season. [American: 2014]
Note: due to the COVID-19 pandemic, the AAP recommends potentially modifying the start date of palivizumab treatment to correspond with the start of RSV, even if in spring or summer. They also recommend >5 doses if the RSV season is especially prolonged, though there is insufficient data for this recommendation. Updated Guidance: Use of Palivizumab Prophylaxis to Prevent Hospitalization From Severe Respiratory Syncytial Virus Infection During the 2022-2023 RSV Season (AAP)

Development

Children born prematurely, particularly those born extremely early, often experience developmental delays. For some children, these delays will resolve over time; others will have lifelong disabilities. Early detection and intervention are the primary care provider's responsibility. According to the AAP's recommended schedule for developmental screening (see Developmental Screening), the primary care clinician should perform developmental surveillance and screening at the child's adjusted age rather than chronologic age until reaching 30 months. Use formal developmental screening tools at the 9-, 18-, and 30-month health supervision visits. [Hagan: 2008] Autism Screening should be performed at the 18-month visit (adjusted age) and again at either the 24- or 30-month visits. [Hyman: 2020] Children born preterm have a higher risk of developing an autism spectrum disorder than children born at term. [Crump: 2021] Any time caregivers are concerned about the child's emotional and/or behavioral development, consider further evaluation for autism, attention, or mood disorders. (See Infant & Early Childhood Social-Emotional Screening for information about response to positive screens.)
When a delay is recognized, further evaluation may be warranted (e.g., hearing testing for the child with speech/language delay or neurologic evaluation for abnormalities of movement, muscle tone, or limb asymmetry). Sometimes, the child just needs time to "catch up." More testing may be performed through Early Intervention (available until age 3), the public school district, and other developmental specialists. Children enrolled in Neonatal Follow-Up Programs will undergo formal developmental testing.
Typical and Atypical Motor Development Videos (Pathways.org) has three 12-minute videos comparing typically developing and atypically developing children at 2 months, 4 months, and 6 months old. 0-3 Months Milestones (pathways.org) lists milestones for 0-3 years. The Milestone Tracker App (CDC) app is a helpful tool for families to track developmental progress over time, but caution must be given to the parents to use the child's adjusted age when viewing the app.

Communication

Graduates from the NICU are at high risk for communicative disorders such as:
  • Delayed early language development
  • Auditory processing deficits, generally diagnosed starting at age 7
  • Difficulties with articulation or production of speech sounds
  • Motor speech disorders of apraxia and dysarthria
  • Voice problems due to vocal cord paralysis or velopharyngeal incompetence
  • Social communication delays
Parents should be educated about speech and language milestones and guided in modeling and language stimulation activities. When appropriate, home programs to work on specific deficit skills can be developed. Occasionally, significant motor impairment necessitates the use of augmentative communication devices.

Learning/Education/Schools

All preterm infants carry some risk for executive function and learning difficulties at school age. This may first be identified when the child is not performing at a peer grade level and is having difficulties with reading and mathematics skills.
Even those with average intelligence and cognitive scores can have subtle learning disabilities that affect functioning in the regular classroom and require additional educational support. Following records of developmental screenings and evaluations, progress with early intervention or developmental therapies, and educational assessments and performance enables early recognition of problems and the need for further intervention. Sometimes, early indications of a learning disability can be seen at a Neonatal Follow-Up Clinic's 4-year-old cognitive/adaptive testing, and the parents can be informed that they need to follow-up with academic achievement testing and cognitive testing in the early elementary school years. Evaluation of learning difficulties may be performed at the school district.
For those who qualify, the public school district's Special Education Services may include:
  • Developmental preschool: Developmental preschool is provided by the public school district in which the family resides for children over age 3 with developmental delays. Developmental preschool provides a structured learning environment with peer interaction and modeling by "typically" developing children. Therapies such as physical, occupational, and speech-language therapy are provided in the school setting when needed. Parental support is provided to families as well. The local school district operates these programs.
  • Specialized kindergarten: Available through the public school system to help kindergarten-age children who need special services. These programs go by various names, such as "Diagnostic Kindergarten."
  • Elementary and secondary school resources: Resources for learning disabilities are usually established around 7 years of age when IQ scores have become more reliable (barring extreme environmental challenges), and IQ subtests and academic achievement tests can distinguish learning strengths and weaknesses, which may respond to specialized instruction
  • To determine if a child qualifies for special education services, a parent may request a free developmental or psychoeducational evaluation from the school district in which they reside. Medical providers who diagnose or suspect a child has a disability may also request an evaluation as outlined in IIDEA Parent Guide (National Center for Learning Disabilities) (PDF Document 1.1 MB). Child Find requires all school districts to identify, locate, and evaluate all children with disabilities.

Mental Health/Behavior

Behavioral problems, including ADHD, anxiety, and autism, are common among preterm infants in early childhood as well as during school years and should be evaluated and treated in the same manner as for any other child. If there are behavioral concerns, be sure to assess for the following medical concerns that may cause or contribute to behavioral problems in former premature infants:
  • Inadequate sleep: Sleep Medications and Sleep Issues provide further diagnosis and management information.
  • Constipation: Constipation provides further diagnosis and management information.
  • Seizures: Seizures/Epilepsy provides further diagnosis and management information.
  • Side effects of medications
  • Gastroesophageal reflux: Gastroesophageal Reflux Disease provides further diagnosis and management information.
  • Skin conditions causing chronic irritation: Skin and Wound Care for CYSHCN provides further diagnosis and management information.
  • Chronic ear infections and other sources of pain
  • Physical neglect, sexual or other physical abuse: Foster Care provides further diagnosis and management information for these toxic stress issues.
  • Oral aversion: feeding refusal. See Nutrition/Growth/Bone.
If primary care management of these issues and behavior problems proves unsuccessful, referral should be considered. The Medical Home Portal has diagnosis and management modules for Autism Spectrum Disorder and Anxiety Disorders.

Eyes/Vision

Preterm infants are at risk for many problems that affect vision, including retinopathy of prematurity (ROP), strabismus, cortical visual impairment, and problems with visual acuity.
Retinopathy of prematurity (ROP)
Each year in the United States, 14,000-16,000 infants develop retinopathy of prematurity (ROP), characterized by abnormal retinal vascularization in preterm infants; of these infants, approximately 400-650 become legally blind (>20/200). Infants less than 30 weeks or below 1500 grams should be screened for ROP because timely laser treatment decreases the risk of blindness from ROP by about 50%. [Fierson: 2018] Even infants cleared of ROP in the NICU should be periodically followed by an ophthalmologist. Premature Infant and Retinopathy of Prematurity provides further information.
Strabismus
Strabismus is the improper alignment of the eyes. It can lead to diminished visual acuity and depth perception. Refer infants, young children, and those with developmental delays to a pediatric ophthalmologist for diagnosis and management; an optometrist may evaluate older, cooperative children.
Cortical visual impairment (CVI)
CVI is a decreased visual response due to a neurological problem affecting the visual part of the brain. With CVI, either the eye exam is normal, or the child has an eye condition that cannot account for the abnormal visual behavior. [American: 2019] This condition used to be called cortical blindness, which is misleading since vision can improve with time. Several conditions in preterm infants place them at increased risk of complications, such as:
  • <1500 grams
  • <32 weeks
  • High-grade IVH
  • Hydrocephalus
  • Severe illness (the need for ECMO)
  • Hypoxia
  • Infection, particularly CNS infection
  • Periventricular leukomalacia (PVL)
  • Stroke
Many premature infants will receive their initial ophthalmologic exam in the NICU. Primary care providers can work with families to establish an ophthalmologic follow-up plan and to monitor for changes through routine vision screening and eye exams.

Ears/Hearing

Hearing screening is typically performed prior to discharge in the NICU, but premature infants are at increased risk of hearing impairment, including later-onset and progressive hearing loss and auditory neuropathy. Contributing factors that can increase risk include:
  • Extreme prematurity, as well as prolonged oxygen use
  • Infants with a history of in-utero infections, such as cytomegalovirus, rubella, syphilis, herpes, or toxoplasmosis
  • Infants who have received certain antibiotics, have received extracorporeal membrane oxygenation (ECMO), or have suffered other neurological complications.
Refer for diagnostic audiology testing all infants who stayed in the NICU 5 days or more, were exposed to ototoxic medications, or who have other risk factors, congenital infections, or parental concerns. [Harlor: 2009] [Joint: 2019] See Hearing Screening for more information.
If hearing loss is identified, the first steps in assisting the child and family include:
  • Educating the family regarding the need for:
  • Speech and language therapy
  • Hearing amplification to overcome hearing loss
  • Evaluation by an Ear, Nose, and Throat Specialist (ENT)
  • Early intervention services
  • Providing information about communication options and hearing technologies
  • Evaluating for associated medical conditions, such as heart arrhythmias, vision problems, and kidney problems
Hearing Loss and Deafness provides further diagnosis and management information.

Musculoskeletal

There are a number of musculoskeletal findings that can develop in premature infants, including head shape deformities, craniosynostosis, torticollis, and developmental dysplasia of the hip.
Head and neck
Head deformation occurs in just under 1 out of 5 term infants; in infants born prematurely, that rate is higher. [Rogers: 2011] Plagiocephaly, or asymmetric flattening of the posterior skull, is common due to lying in a supine position. Dolichocephaly (narrow biparietal or side-to-side measurement with an elongated skull) is now less common with developmental care in the NICU. Often, head shape variation is a cosmetic issue and requires no treatment. However, there are circumstances when further evaluation should be undertaken, and treatment with a helmet is considered. [Rogers: 2011] Craniosynostosis, or early closure of 1 or more cranial sutures, can look similar to some types of deformational abnormalities.
  • Visually inspect for plagiocephaly, brachycephaly, or asymmetry. Palpate for premature fusion of sutures (craniosynostosis, or early closure of 1 or more cranial sutures, is far less common for both preterm and term infants but can look similar to some types of deformational abnormalities.) See Cranial Deformation and Craniosynostosis. Advise against using head-shaping pillows and positioners due to safety concerns.
  • Palpate for tight neck muscles (torticollis) and ask about a preference to position the head in one direction. Advise range of motion exercises as the infant matures, such as "tummy time," with the head positioned to each side when prone.
Hips, extremities, and spine
Formation of the bones and muscles is generally unaffected by premature birth. As with term infants, parents may need reassurance about the relative bow-legged appearance of their infant. Hip exams should be performed at routine intervals for the first 1-2 years, and those with suspected hip dysplasia or abnormal hip exams should be referred for imaging and specialist consultation. When performing screening imaging for hip dysplasia based on risk factors such as breech positioning or sibling with hip dysplasia, imaging should be completed at intervals adjusted for prematurity. For children with cerebral palsy or congenital malformations, the medical home provider should work with a team of specialists to evaluate and manage the condition. See cerebral palsy for more information on diagnosis and management.

Dental

Because infants born preterm are at increased risk for enamel hypoplasia and dental defects, good dental hygiene and dental health-promoting practices within a pediatric dental home are especially important. A narrow palate is common and can cause difficulties moving food in the mouth and contribute to short-term feeding difficulties. It is presumed to be a result of orotracheal intubation. [Hohoff: 2005] [Paulsson: 2004] Teething may occur following corrected gestational age, but the age ranges vary. It is not known what the long-term consequences of prematurity are on the palate or its morphology and the need for treatment such as orthodontia. Advise that infants born prematurely see a dentist by 1 year of age or after the eruption of the first tooth. [Schaaf: 2011]

Dermatology

Scars
Surgical scars and traumatic scars from intravenous (IV) infiltrations and other mishaps related to very fragile skin may be seen. Remind families to protect scars with sunblock during periods of sun exposure.
  • PDA ligation results in a relatively large scar on the left posterior and lateral chest wall.
  • Inguinal hernia repair scars are often hard to detect as they are made along the skin fold lines in the groin.
  • Incision scars related to IV catheters may be found on the wrists and ankles.
  • Exploratory laparotomy and resection of bowel due to necrotizing enterocolitis (NEC) may leave abdominal scars.
Ostomies
If the infant has an ostomy, periodically visualize the skin around the tube by removing the dressing. See Feeding Tubes & Gastrostomies in Children and Tracheostomy.

Endocrine/Metabolism

Certain endocrine disorders, including hypoglycemia and cortisol deficiency, may be detected in the NICU but infrequently require outpatient follow-up after discharge.

Services & Referrals

The following lists resources that may be particularly helpful for finding services related to premature infant follow-up:

Audiology (see NW providers [3])

Refer for testing and evaluation of hearing at all ages; assistance in selecting, fitting, and counseling related to the use of augmentative hearing devices; and for mapping for cochlear implants.

Behavioral Therapies (see NW providers [1])
Refer children who need assistance with specific behaviors, mood disorders, or problem-solving skills. Children with autism spectrum disorder benefit from Applied Behavioral Analysis.

Developmental - Behavioral Pediatrics (see NW providers [1])
Refer for assistance in evaluating children with more complex developmental and behavioral problems. They assist with an overall diagnosis and help with specific recommendations for therapy but do not typically provide ongoing primary care.

Early Intervention for Children with Disabilities/Delays (see NW providers [3])
Refer when an infant or toddler under 36 months of age needs further assessment for possible developmental delays in cognitive, social, communication, and/or motor skills. Premature infants may qualify for Early Intervention based solely on their risk of developmental delays. Refer infants or children under the age of 3 with visual, speech, or language impairment.

General Counseling Services (see NW providers [1])
Refer children who need private therapy for specific behaviors, mood disorders, or problem-solving skills. For delayed social skills, evaluation may be useful. Access varies with family’s income and insurance.

Head Start/Early Head Start (see NW providers [0])
Refer children ages 0-5 from low-income families for this federally funded school readiness program that can help with areas of non-severe delay, such as speech articulation, developing play skills, or decreasing aggression. This is generally not a placement for children with autism.

Medical Genetics (see NW providers [1])
Offer a consultation with a geneticist or genetic counselor when there is concern of a genetic abnormality that may be contributing to the infant’s preterm condition and/or complications.

Mental Health Evaluation/Assessment (see NW providers [0])
Referral can be useful for evaluation of delayed social skills.

Neonatal Follow-up Programs (see NW providers [0])
The NICU typically does referral based on inclusion criteria, such as extreme prematurity. Primary care clinicians can also refer eligible premature infants for additional assessment and care coordination. The services/disciplines offered may include medical evaluation, physical therapy, occupational therapy, developmental psychology, speech pathology, and neurology.

Occupational Therapy (see NW providers [1])
Refer for feeding therapy. The training backgrounds of feeding therapists vary and may include occupational therapists, speech-language pathologists, or developmental therapists; additional training in feeding therapy is optimal.

Pediatric Cardiology (see NW providers [0])
Consult for assistance in diagnosing and managing persistent cardiovascular problems, such as pulmonary hypertension or persistent ductal or septal defects, and for determining timing of surgery.

Pediatric Dentistry (see NW providers [2])
Referral is helpful for infants and children with abnormal dentition or sensory issues affecting their ability to cooperate with dental care and examinations.

Pediatric Gastroenterology (see NW providers [0])
Refer for evaluation and the collaborative management of necrotizing enterocolitis, short bowel syndrome, congenital gastrointestinal abnormalities with perforation, or failure to thrive.

Pediatric Nephrology (see NW providers [0])
Consultation is helpful in evaluating and managing kidney and urinary tract issues, such as nephrocalcinosis, hypertension, reflux, and abnormal kidney function.

Pediatric Neurology (see NW providers [0])
Consult for assistance with initial diagnosis of cerebral palsy, evaluation of unusual or atypical tone and movement patterns, and management of seizures.

Pediatric Neurosurgery (see NW providers [1])
Refer for shunt management and ongoing evaluation of hydrocephalus, as well as evaluation of atypical head shape.

Pediatric Ophthalmology (see NW providers [1])
Refer for expertise in evaluating and managing ophthalmologic complications of prematurity, especially retinopathy of prematurity and strabismus. Premature infants with retinopathy of prematurity should be referred even if cleared of the ROP in the NICU.

Pediatric Orthopedics (see NW providers [4])
Refer for help managing congenital malformations, suspected hip or spine problems, and for routine care and management of children with cerebral palsy.

Pediatric Physical Medicine & Rehabilitation (see NW providers [3])
Refer to pediatric rehabilitation (“rehab") doctors or physiatrists for more in-depth assessment of musculoskeletal, neurologic, genetic, or conditions resulting in abnormal muscle tone and spasticity, such as cerebral palsy.

Pediatric Plastic Surgery (see NW providers [3])
Refer to a plastic surgeon, neurosurgeon, or craniofacial specialist to evaluate and manage cranial deformities.

Pediatric Urology (see NW providers [0])
Refer for evaluation and surgical management of persistent urologic problems such as urinary reflux, posterior urethral valves and hydronephrosis, inguinal hernias, or persistent hydroceles.

Physical Therapy (see NW providers [0])
Referral can help evaluate delays in gross motor function, improving mobility, and customizing devices that enhance mobility.

Speech - Language Pathologists (see NW providers [4])
Refer children with speech disorders or language delays whose needs are not adequately met through Early Intervention and the public school system as part of Special Education services. Speech and language therapists may be accessed through referrals to private therapists or through community-based and not-for-profit programs.

ICD-10 Coding

  • P07.0x, Extremely low birth weight newborn (up to 999 grams)
  • P07.1x, Other low birth weight newborn (1000-2499 grams)
  • P07.2x, Extreme immaturity of newborn (through 27 completed weeks)
  • P07.3x, Preterm (premature) newborn (28-36 6/7 completed weeks)

The last digit, represented above as an "x," signifies the need for further coding details about weight or gestational age. Coding for Disorders of Newborn Related to Short Gestation and Low Birth Weight (icd10data.com) provides these coding details.

Resources

Information & Support

Related Portal Content

The following Portal topics contain diagnosis and management information for conditions often related to premature infant follow-up care:

Answers to questions that families may frequently ask can be found at:

The Care Notebook may also be helpful for tracking medical history, test results, and records.

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For Professionals

Follow-Up of the NICU Patient (Medscape)
Includes information about areas of assessment, long-term monitoring, testing, and outcomes.

Neonatal Hypertension (Medscape)
Provides presentation, diagnosis, and treatment information.

The American Academy of Cerebral Palsy and Developmental Medicine (AACPDM)
Multidisciplinary, scientific education for health professionals and promote excellence in research and services for the benefit of people with and at risk for cerebral palsy and other childhood-onset disabilities.

For Parents and Patients

Find Your Parent Center
Parent Centers provide education and referrals for families with a child who has a disability, as well as the professionals who work with them. There are almost 100 Parent Training and Information Centers (PTIs) and Community Parent Resource Centers (CPRCs) in the US states and Territories; Center for Parent Information & Resources.

Taking Your Preemie Home (KidsHealth)
Information to help parents transition from NICU to home care.

Preemie Milestones (AAP) (PDF Document 824 KB)
Helps parents understand important developmental milestones to watch for at each age and how to determine which milestones to use for preemies; American Academy of Pediatrics, March of Dimes, and National Association of Neonatal Nurses.

Cerebral Palsy Foundation
Nonprofit organization that helps people with cerebral palsy get the interventions and supports they need when they need them.

Patient Education

Tips for Encouraging Speech and Language Development (Pathways.org) (PDF Document 466 KB)
Two-page brochure with speech and hearing milestones and tips for assisting with their development.

Cerebral Palsy Channel; developed by the Cerebral Palsy Foundation
This free app offers information from the world's leading experts on intervention and therapy, communication, building independence, and more.

Tools

Edinburgh Postnatal Depression Scale (PDF Document 120 KB)
A self-administered, 10-question, 5-minute screen for maternal depression with scoring instructions. Free, may be printed without permission.

Edinburgh Postnatal Depression Scale (Spanish) (PDF Document 54 KB)
A Spanish, self-administered, 10-question, 5-minute screen for maternal depression with scoring instructions. Free, may be printed without permission.

Patient Health Questionnaire (PHQ) Screeners
Free screening tools in many languages with scoring instructions to be used by clinicians to help detect mental health disorders. Select from right menu: PHQ, PHQ-9, GAD-7, PHQ-15, PHQ-SADS, Brief PHQ, PHQ-4, PHQ-8.

Screening for Developmental Hip Dysplasia—Clinical Algorithm (AAP)
Algorithm with screening recommendations and recommended actions; American Academy of Pediatrics.

Hammersmith Neurologic Exam (HINE) (PDF Document 254 KB)
This exam consists of 26 items that assess different aspects of neurological function. The HINE is aimed to be used for infants between 3 and 24 months of age.

Services for Patients & Families Nationwide (NW)

For services not listed above, browse our Services categories or search our database.

* number of provider listings may vary by how states categorize services, whether providers are listed by organization or individual, how services are organized in the state, and other factors; Nationwide (NW) providers are generally limited to web-based services, provider locator services, and organizations that serve children from across the nation.

Studies

Clinical Trials for Preterm Infants (clinicaltrials.gov)
Studies looking at better understanding, diagnosing, and treating this condition; from the National Library of Medicine.

Helpful Articles

TeKolste T, Bragg J, Wendel S.
Extremely Low Birth Weight NICU Graduate.
2004; Washington State Department of Health, Children with Special Health Care Needs Program; https://depts.washington.edu/dbpeds/ELBW-NICU-Graduate.pdf
Supplement to: Low Birth Weight Neonatal Intensive Care Graduate. Specifically addresses post-NICU care of ELBW infants who: 1) experienced the usual complications associated with extreme prematurity and/or extreme low birth weight, and 2) were discharged home in a relatively healthy condition.

Villar J, Giuliani F, Barros F, Roggero P, Coronado Zarco IA, Rego MAS, Ochieng R, Gianni ML, Rao S, Lambert A, Ryumina I, Britto C, Chawla D, Cheikh Ismail L, Ali SR, Hirst J, Teji JS, Abawi K, Asibey J, Agyeman-Duah J, McCormick K, Bertino E, Papageorghiou AT, Figueras-Aloy J, Bhutta Z, Kennedy S.
Monitoring the Postnatal Growth of Preterm Infants: A Paradigm Change.
Pediatrics. 2018;141(2). PubMed abstract

Authors & Reviewers

Initial publication: December 2013; last update/revision: September 2023
Current Authors and Reviewers:
Authors: Sarah Winter, MD
Christopher Torsitano, MD
Reviewer: Mary Ann Nelin, MD
Authoring history
2020: update: Jennifer Goldman, MD, MRP, FAAPA; Molly O'Gorman, MDR
2020: update: Sarah Winter, MDA; Mary Ann Nelin, MDA; Annette Haban Bartz, MS, RD, LD, CLCCA; Khanh Lai, MD, FAAPR; Erin Clark, MDR
2015: first version: Jennifer Goldman, MD, MRP, FAAPA; Sarah Winter, MDA; Mary Ann Nelin, MDR
AAuthor; CAContributing Author; SASenior Author; RReviewer

Page Bibliography

ACOG.
ACOG Committee Opinion No 579: Definition of term pregnancy.
Obstet Gynecol. 2013;122(5):1139-40. PubMed abstract / Full Text
For the press release of the definition change, see http://www.acog.org/About-ACOG/News-Room/News-Releases/2013/Ob-Gyns-Redefine-Meaning-of-Term-Pregnancy

American Academy of Pediatrics.
Updated guidance for palivizumab prophylaxis among infants and young children at increased risk of hospitalization for respiratory syncytial virus infection.
Pediatrics. 2014;134(2):415-20. PubMed abstract

American Association for Pediatric Ophthalmology and Strabismus.
Cortical Visual Impairment.
(2019) https://aapos.org/glossary/cortical-visual-impairment. Accessed on 07/08/2020.

Bell EF, Hintz SR, Hansen NI, Bann CM, Wyckoff MH, DeMauro SB, Walsh MC, Vohr BR, Stoll BJ, Carlo WA, Van Meurs KP, Rysavy MA, Patel RM, Merhar SL, Sánchez PJ, Laptook AR, Hibbs AM, Cotten CM, D'Angio CT, Winter S, Fuller J, Das A.
Mortality, In-Hospital Morbidity, Care Practices, and 2-Year Outcomes for Extremely Preterm Infants in the US, 2013-2018.
JAMA. 2022;327(3):248-263. PubMed abstract / Full Text

Boguszewski MCS.
Growth hormone deficiency and replacement in children.
Rev Endocr Metab Disord. 2021;22(1):101-108. PubMed abstract

Bright FM, Vink R, Byard RW, Duncan JR, Krous HF, Paterson DS.
Abnormalities in substance P neurokinin-1 receptor binding in key brainstem nuclei in sudden infant death syndrome related to prematurity and sex.
PLoS One. 2017;12(9):e0184958. PubMed abstract / Full Text

Byrne R, Noritz G, Maitre NL.
Implementation of Early Diagnosis and Intervention Guidelines for Cerebral Palsy in a High-Risk Infant Follow-Up Clinic.
Pediatr Neurol. 2017;76:66-71. PubMed abstract

Callaghan WM, MacDorman MF, Shapiro-Mendoza CK, Barfield WD.
Explaining the recent decrease in US infant mortality rate, 2007-2013.
Am J Obstet Gynecol. 2017;216(1):73.e1-73.e8. PubMed abstract / Full Text

Committee on Quality Improvement, Subcommittee on Developmental Dysplasia of the Hip.
Clinical practice guideline: early detection of developmental dysplasia of the hip. Committee on Quality Improvement, Subcommittee on Developmental Dysplasia of the Hip. American Academy of Pediatrics.
Pediatrics. 2000;105(4 Pt 1):896-905. PubMed abstract

Crump C, Sundquist J, Sundquist K.
Preterm or Early Term Birth and Risk of Autism.
Pediatrics. 2021;148(3). PubMed abstract / Full Text

D'Agostino JA.
An evidentiary review regarding the use of chronological and adjusted age in the assessment of preterm infants.
J Spec Pediatr Nurs. 2010;15(1):26-32. PubMed abstract / Full Text

D'Agostino JA, Passarella M, Martin AE, Lorch SA.
Use of Gastroesophageal Reflux Medications in Premature Infants After NICU Discharge.
Pediatrics. 2016;138(6). PubMed abstract / Full Text

Earls MF, Yogman MW, Mattson G, Rafferty J.
Incorporating recognition and management of perinatal and postpartum depression into pediatric practice.
Pediatrics. 2019. PubMed abstract / Full Text

Eds CP Howson, MV Kinney, JE Lawn. World Health Organization.
Born too soon: the global action report on preterm birth.
March of Dimes, PMNCH, Save the Children, WHO. Geneva, 2012.

Ferré C, Callaghan W, Olson C, Sharma A, Barfield W.
Effects of Maternal Age and Age-Specific Preterm Birth Rates on Overall Preterm Birth Rates - United States, 2007 and 2014.
MMWR Morb Mortal Wkly Rep. 2016;65(43):1181-1184. PubMed abstract

Fierson WM.
Screening Examination of Premature Infants for Retinopathy of Prematurity.
Pediatrics. 2018;142(6). PubMed abstract

Fischler B, Lamireau T.
Cholestasis in the newborn and infant.
Clin Res Hepatol Gastroenterol. 2014;38(3):263-7. PubMed abstract

Flynn J.
Neonatal hypertension.
Medscape; (2016) http://emedicine.medscape.com/article/979588-overview. Editor: Rosenkrantz T; Contributors: Pramanik A, Windle ML. Accessed on 7/8/2020.

Fraga JC, Jennings RW, Kim PC.
Pediatric tracheomalacia.
Semin Pediatr Surg. 2016;25(3):156-64. PubMed abstract

Hagan JF, Shaw JS, Duncan PM, eds. .
Bright Futures: Guidelines for Health Supervision of Infants, Children, and Adolescents.
3rd ed. Elk Grove Village, IL: American Academy of Pediatrics; 2008. 978-1-58110-223-9 http://brightfutures.aap.org/
Authoritative compilation of guidelines and evidence for health supervision, including developmental surveillance and screening, physical exam, laboratory and other testing, and anticipatory guidance. The Affordable Care Act of 2010 cites Bright Futures as the standard for well child and adolescent care.

Hamrick SEG, Sallmon H, Rose AT, Porras D, Shelton EL, Reese J, Hansmann G.
Patent Ductus Arteriosus of the Preterm Infant.
Pediatrics. 2020;146(5). PubMed abstract / Full Text

Harlor AD Jr, Bower C.
Hearing assessment in infants and children: recommendations beyond neonatal screening.
Pediatrics. 2009;124(4):1252-63. PubMed abstract / Full Text

Hayes D Jr, Wilson KC, Krivchenia K, Hawkins SMM, Balfour-Lynn IM, Gozal D, Panitch HB, Splaingard ML, Rhein LM, Kurland G, Abman SH, Hoffman TM, Carroll CL, Cataletto ME, Tumin D, Oren E, Martin RJ, Baker J, Porta GR, Kaley D, Gettys A, Deterding RR.
Home Oxygen Therapy for Children. An Official American Thoracic Society Clinical Practice Guideline.
Am J Respir Crit Care Med. 2019;199(3):e5-e23. PubMed abstract / Full Text

Higgins RD, Jobe AH, Koso-Thomas M, Bancalari E, Viscardi RM, Hartert TV, Ryan RM, Kallapur SG, Steinhorn RH, Konduri GG, Davis SD, Thebaud B, Clyman RI, Collaco JM, Martin CR, Woods JC, Finer NN, Raju TNK.
Bronchopulmonary Dysplasia: Executive Summary of a Workshop.
J Pediatr. 2018;197:300-308. PubMed abstract / Full Text

Hohoff A, Rabe H, Ehmer U, Harms E.
Palatal development of preterm and low birthweight infants compared to term infants - What do we know? Part 2: The palate of the preterm/low birthweight infant.
Head Face Med. 2005;1:9. PubMed abstract / Full Text

Hyman SL, Levy SE, Myers SM.
Identification, Evaluation, and Management of Children With Autism Spectrum Disorder.
Pediatrics. 2020;145(1). PubMed abstract / Full Text
Comprehensive clinical report addressing the prevalence, clinical symptoms, screening and diagnosis, etiologic evaluation, and interventions for children with autism spectrum disorder.

Institute of Medicine (US) Committee on Understanding Premature Birth and Assuring Healthy Outcomes.
Preterm Birth: Causes, Consequences, and Prevention.
Washington DC: National Academies Press; 2007. 978-0-309-10159-2 http://www.ncbi.nlm.nih.gov/books/NBK11362/
The extensive report provides information on risk factors and suggested strategies to reduce preterm births.

International Research Group.
Tiny Baby Collaborative.
(2023) https://www.tinybabycollaborative.org/. Accessed on Sept 2023.

Jabbour J, Robey T.
Resolution of vocal fold immobility in preterm infants.
Int J Pediatr Otorhinolaryngol. 2017;103:83-86. PubMed abstract

Joint.
Year 2019 Position Statement: Principles and Guidelines for Early Hearing Detection and Intervention Programs.
Journal of Early Hearing Detection and Intervention. 2019;4(2):1-44. / Full Text

Joint Committee on Infant Hearing.
Year 2019 position statement: Principles and guidelines for early hearing detection and intervention programs.
Journal of Early Hearing Detection and Intervention. 2019. / Full Text

Journal of Early Hearing Detection and Intervention.
Position Statement: Principles and Guidelines for Early Hearing Detection and Intervention Programs.
National Center for Hearing Assessment and Management - Utah State University. 2019. / https://digitalcommons.usu.edu/jehdi/vol4/iss2/1/

Kumar VH, Clive J, Rosenkrantz TS, Bourque MD, Hussain N.
Inguinal hernia in preterm infants (< or = 32-week gestation).
Pediatr Surg Int. 2002;18(2-3):147-52. PubMed abstract

Lahood A., Bryant, C.
Outpatient Care of the Premature Infant.
American Family Physician. 2007;76(8). / Full Text

Lapillonne A, O'Connor DL, Wang D, Rigo J.
Nutritional recommendations for the late-preterm infant and the preterm infant after hospital discharge.
J Pediatr. 2013;162(3 Suppl):S90-100. PubMed abstract

Lightdale JR, Gremse DA.
Gastroesophageal reflux: management guidance for the pediatrician.
Pediatrics. 2013;131(5):e1684-95. PubMed abstract

Lowry RB, Renwick DH.
Relative frequency of the Hurler and Hunter syndromes.
N Engl J Med. 1971;284(4):221-2. PubMed abstract

Mathews TJ, Driscoll AK.
Trends in Infant Mortality in the United States, 2005-2014.
NCHS Data Brief. 2017(279):1-8. PubMed abstract

McInerny T, Adam H, Campbell D, Kamat D, Kelleher K.
American Academy of Pediatrics Textbook of Pediatric Care.
1st Chapter 216 ed. American Academy of Pediatrics; 2008. 1581102682 http://www.amazon.com/American-Academy-Pediatrics-Textbook-Pediatric/d...

National Center for Health Statistics.
Births and Natality.
Centers for Disease Control and Prevention; (2020) https://www.cdc.gov/nchs/fastats/births.htm. Accessed on July 2020.

Nickavar A, Assadi F.
Managing hypertension in the newborn infants.
Int J Prev Med. 2014;5(Suppl 1):S39-43. PubMed abstract / Full Text

Novak I, Morgan C, Adde L, Blackman J, Boyd RN, Brunstrom-Hernandez J, Cioni G, Damiano D, Darrah J, Eliasson AC, de Vries LS, Einspieler C, Fahey M, Fehlings D, Ferriero DM, Fetters L, Fiori S, Forssberg H, Gordon AM, Greaves S, Guzzetta A, Hadders-Algra M, Harbourne R, Kakooza-Mwesige A, Karlsson P, Krumlinde-Sundholm L, Latal B, Loughran-Fowlds A, Maitre N, McIntyre S, Noritz G, Pennington L, Romeo DM, Shepherd R, Spittle AJ, Thornton M, Valentine J, Walker K, White R, Badawi N.
Early, Accurate Diagnosis and Early Intervention in Cerebral Palsy: Advances in Diagnosis and Treatment.
JAMA Pediatr. 2017;171(9):897-907. PubMed abstract

Nwafor-Anene VN, DeCristofaro JD, Baumgart S.
Serial head ultrasound studies in preterm infants: how many normal studies does one infant need to exclude significant abnormalities?.
J Perinatol. 2003;23(2):104-10. PubMed abstract

Olsen R, Greisen G, Schrøder M, Brok J.
Prophylactic Probiotics for Preterm Infants: A Systematic Review and Meta-Analysis of Observational Studies.
Neonatology. 2016;109(2):105-12. PubMed abstract

Osterman MJK, Hamilton BE, Martin JA, Driscoll AK, Valenzuela CP.
Births: Final Data for 2021.
Natl Vital Stat Rep. 2023;72(1):1-53. PubMed abstract / Full Text

Paulsson L, Bondemark L, Söderfeldt B.
A systematic review of the consequences of premature birth on palatal morphology, dental occlusion, tooth-crown dimensions, and tooth maturity and eruption.
Angle Orthod. 2004;74(2):269-79. PubMed abstract

Phillips RM, Goldstein M, Hougland K, Nandyal R, Pizzica A, Santa-Donato A, Staebler S, Stark AR, Treiger TM, Yost E.
Multidisciplinary guidelines for the care of late preterm infants.
J Perinatol. 2013;33 Suppl 2:S5-22. PubMed abstract / Full Text
Gives guidelines for caring for late preterm infants in the hospital and after discharge. Includes short- and long-term follow up; each care recommendation is associated with counseling points to share with the family.

Pickering LK, Baker CJ, Kimberlin DW, Long SS ed.
Red Book: 2012 Report of the Committee on Infectious Diseases.
29th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2012. 158110703X

Rogers GF.
Deformational plagiocephaly, brachycephaly, and scaphocephaly. Part I: terminology, diagnosis, and etiopathogenesis.
J Craniofac Surg. 2011;22(1):9-16. PubMed abstract

Rogers GF.
Deformational plagiocephaly, brachycephaly, and scaphocephaly. Part II: prevention and treatment.
J Craniofac Surg. 2011;22(1):17-23. PubMed abstract

Saari TN.
Immunization of preterm and low birth weight infants. American Academy of Pediatrics Committee on Infectious Diseases.
Pediatrics. 2003;112(1 Pt 1):193-8. PubMed abstract / Full Text

Sauve R.
Routine screening cranial ultrasound examinations for the prediction of long term neurodevelopmental outcomes in preterm infants.
Paediatr Child Health. 2001;6(1):39-52. PubMed abstract / Full Text

Schaaf CP, Scott DA, Wiszniewska J, Beaudet AL.
Identification of incestuous parental relationships by SNP-based DNA microarrays.
Lancet. 2011;377(9765):555-6. PubMed abstract

Shakir AK, Altaf MA.
Azithromycin Induces Migrating Motor Complexes in Pediatric Patients Undergoing Antroduodenal Motility Studies.
J Pediatr Pharmacol Ther. 2018;23(5):390-394. PubMed abstract / Full Text

Tauber KA.
Persistent newborn pulmonary hypertension.
Medscape; (2019) http://emedicine.medscape.com/article/898437-overview. Editors: Windle ML, Pramanik AK; Chief Editor: Berger S; Contributors: Steinhorn RH. Accessed on 7/8/2020.

TeKolste T, Bragg J, Wendel S.
Extremely Low Birth Weight NICU Graduate.
2004; Washington State Department of Health, Children with Special Health Care Needs Program; https://depts.washington.edu/dbpeds/ELBW-NICU-Graduate.pdf
Supplement to: Low Birth Weight Neonatal Intensive Care Graduate. Specifically addresses post-NICU care of ELBW infants who: 1) experienced the usual complications associated with extreme prematurity and/or extreme low birth weight, and 2) were discharged home in a relatively healthy condition.

Trachtenbarg DE, Golemon TB.
Care of the premature infant: Part I. Monitoring growth and development.
Am Fam Physician. 1998;57(9):2123-30. PubMed abstract / Full Text

Villar J, Giuliani F, Barros F, Roggero P, Coronado Zarco IA, Rego MAS, Ochieng R, Gianni ML, Rao S, Lambert A, Ryumina I, Britto C, Chawla D, Cheikh Ismail L, Ali SR, Hirst J, Teji JS, Abawi K, Asibey J, Agyeman-Duah J, McCormick K, Bertino E, Papageorghiou AT, Figueras-Aloy J, Bhutta Z, Kennedy S.
Monitoring the Postnatal Growth of Preterm Infants: A Paradigm Change.
Pediatrics. 2018;141(2). PubMed abstract

Wadon M, Modi N, Wong HS, Thapar A, O'Donovan MC.
Recent advances in the genetics of preterm birth.
Ann Hum Genet. 2020;84(3):205-213. PubMed abstract / Full Text

Wilson SL, Cradock MM.
Review: Accounting for prematurity in developmental assessment and the use of age-adjusted scores.
J Pediatr Psychol. 2004;29(8):641-9. PubMed abstract / Full Text

Yee WH, Soraisham AS, Shah VS, Aziz K, Yoon W, Lee SK.
Incidence and timing of presentation of necrotizing enterocolitis in preterm infants.
Pediatrics. 2012;129(2):e298-304. PubMed abstract / Full Text