Impact of neonatal intensive care on late preterm infants: developmental outcomes at 3 years

The weight for length in late preterm infants assessed with bioelectrical impedance is positively associated with anthropometric variables

INTRODUCTION

The fat mass (FM) is greater in late preterm than full term infants at 1 month post birth, which may be an additional risk factor for metabolic syndrome in adulthood.

OBJETIVES

To evaluate body composition (BC) in late preterm infants using bioelectrical impedance analysis (BIA) to determine which anthropometric parameters are associated with BC. Our hypothesis was that weight-for-length is associated with the length-normalized fat mass index (FMI) at 1 year of life.

MATERIALS AND METHODS

We carried out a prospective cohort study in 2 groups: late preterm infants and full term infants. We obtained BC data by BIA. We calculated the fat mass (FM), FMI, fat-free mass (FFM) and length-normalized fat-free mass index (FFMI) at 1, 6 and 12 months of life. After, we assessed the association of the FMI with anthropometric parameters using multiple linear regression analysis.

RESULTS

The study included 97 late preterm and 47 full term infants, although at 12 months of life, the BC assessment was performed on 66 and 33 infants, respectively. Late preterm infants, compared to full term infants, had a higher FFM at 1 month (4013 vs 3524 g), a higher weight velocity at 6 months (5480 g versus 4604 g) and a lower FFM (7232 vs 7813 g) and FFMI (12.55 vs 13.26) at 12 months of life. The multivariate regression analysis showed that the weight-for-length z-core at 12 months was positively associated with the FMI at 12 months in all infants.

CONCLUSION

The weight-for-length z-score at 12 months is strongly associated with the FMI at 1 year of life. Further studies are needed to investigate whether an increment in this anthropometric parameter may modulate the risk of chronic diseases.

Association between Neonatal Intensive Care Unit Admission and Supine Sleep Positioning, Breastfeeding, and Postnatal Smoking among Mothers of Late Preterm Infants

OBJECTIVE

To evaluate the association between neonatal intensive care unit (NICU) admission and breastfeeding practices, infant supine sleep positioning, and postnatal smoking among mothers of late preterm infants.

STUDY DESIGN

Data from 36 states using the 2000-2013 Pregnancy Risk Assessment Monitoring System were analyzed. χ² tests and 95% CI assessed infant and maternal characteristics and recommended care practices for late preterm infants based on NICU admission after birth. Adjusted prevalence ratios (APR) for breastfeeding initiation and continuation at 10 weeks, supine sleep position, and postnatal smoking were estimated using multivariable logistic regression models, controlling for infant and maternal characteristics. Analyses were weighted and SEs accounted for the complex survey design.

RESULTS

Our sample included 62 494 late preterm infants, representing a weighted population of 1 441 451 late preterm infants. In the adjusted analysis, mothers of late preterm infants admitted to a NICU were more likely to initiate breastfeeding (APR 1.07; 95% CI 1.05-1.09) and place their infants in supine sleep position (1.04; 95% CI 1.01-1.06) than mothers of late preterm infants not admitted to a NICU. There was no significant difference between groups for breastfeeding continuation or postnatal smoking.

CONCLUSIONS

Mothers of late preterm infants admitted to a NICU were more likely to initiate breastfeeding and practice supine sleep position than mothers of late preterm infants not admitted to a NICU. Future work should seek to identify the drivers of these differences to develop effective strategies to engage mothers in these health promoting infant care practices.

A Follow-Up Study of Cognitive Development in Low Risk Preterm Children

The results of a longitudinal study on the cognitive development of one group of full-term and three groups of low risk preterm children with different gestational ages (GA) are presented. The 181 participants were divided into four GA groups of similar size. The aims were: 1) To check if there are differences in cognitive development (measured through the Batelle scale) among the GA groups. 2) To establish the predictive factors of cognitive development at 22 and 60 months of age, taking into account biomedical, environmental and individual factors. The results of the repeated measures ANOVA performed at 22 and 60 months of age indicated that the cognitive trajectories of the four GA groups were similar. Linear regression analyses showed that the effect of the different predictors changed in relation to the time of measurement of cognitive development. Biological factors and the quality of home environment had a moderate effect on the cognitive development at 22 months of age. Cognitive results obtained at 22 months of age, and, to a lesser extent, working memory had the greatest effect on cognitive development at 60 months. GA does not predict cognitive development. Preterm children do not show cognitive delay if they are healthy.

Feeding the Late and Moderately Preterm Infant: A Position Paper of the European Society for Paediatric Gastroenterology, Hepatology and Nutrition Committee on Nutrition

Nutritional guidelines and requirements for late or moderately preterm (LMPT) infants are notably absent, although they represent the largest population of preterm infants. The European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) Committee on Nutrition (CoN) performed a review of the literature with the aim to provide guidance on how to feed infants born LMPT, and identify gaps in the literature and research priorities.Only limited data from controlled trials are available. Late preterm infants have unique, often unrecognized, vulnerabilities that predispose them to high rates of nutritionally related morbidity and hospital readmissions. They frequently have feeding difficulties that delay hospital discharge, and poorer rates of breastfeeding initiation and duration compared with term infants. This review also identified that moderately preterm infants frequently exhibit postnatal growth restriction.The ESPGHAN CoN strongly endorses breast milk as the preferred method of feeding LMPT infants and also emphasizes that mothers of LMPT infants should receive qualified, extended lactation support, and frequent follow-up. Individualized feeding plans should be promoted. Hospital discharge should be delayed until LMPT infants have a safe discharge plan that takes into account local situation and resources.In the LMPT population, the need for active nutritional support increases with lower gestational ages. There may be a role for enhanced nutritional support including the use of human milk fortifier, enriched formula, parenteral nutrition, and/or additional supplements, depending on factors, such as gestational age, birth weight, and significant comorbidities. Further research is needed to assess the benefits (improved nutrient intakes) versus risks (interruption of breast-feeding) of providing nutrient-enrichment to the LMPT infant.

Neurodevelopmental outcomes of the late preterm infant

Late preterm infants (born at 34^0/7-36^6/7 weeks gestation) have been found to have increased morbidity and mortality compared to full term infants. Research has also been done to explore longer-term neurodevelopmental outcomes. This review details neurodevelopmental outcomes from birth to adulthood for late preterm infants. Outcome studies indicate that they are at increased risk of developmental disability, school failure, behavior problems, social and medical disabilities, and death. Many questions still remain regarding late preterm infant neurodevelopmental outcomes and future research should be done into this topic. Given the high prevalence of late preterm births, even small differences in abilities, special education, and length of education may have broader consequences.

Impact of NICU admission on Colorado-born late preterm infants: breastfeeding initiation, continuation and in-hospital breastfeeding practices

OBJECTIVE

Compare breastfeeding initiation and continuation rates, and in-hospital breastfeeding practices, of late preterm infants (LPIs) cared for in a NICU versus those cared for exclusively in the nursery (non-NICU).

STUDY DESIGN

Using data from the 2009-2014 Colorado Pregnancy Risk Assessment Monitoring System (PRAMS), breastfeeding initiation, continuation, and in-hospital breastfeeding practices of NICU versus non-NICU LPIs (34 0/7 to 36 6/7 weeks gestation, n = 20,767) were analyzed, and multivariate models were created controlling for maternal and infant characteristics.

RESULTS

Mothers of NICU LPIs were equally likely to initiate breastfeeding (APR 1.0; 95% CI 0.95-1.06) but less likely to continue breastfeeding at 10 weeks (APR 0.86; 95% CI 0.76-0.99) compared to mothers of non-NICU LPIs. Mothers of NICU LPIs were less likely to breastfeed in the hospital, less likely to be told to feed infants on demand, and more likely to be given a breast pump during hospitalization.

CONCLUSIONS

There are significant differences in both breastfeeding continuation and several in-hospital breastfeeding practices for NICU versus non-NICU LPIs. Further research is needed so that targeted policies and programs can be developed to improve breastfeeding rates in this vulnerable population.

Impact of neonatal morbidity on the risk of developmental delay in late preterm infants

BACKGROUND

Late preterm infants (LPI) have a higher risk of developmental delay (DD) than term-born infants. The association of perinatal complications with specific morbidity is not clear.

AIM

(1) To compare the risk of DD at 4years of age between LPI who have presence or absence of any morbidity associated with the prematurity at birth, called complicated (cLPI) or uncomplicated (uLPI), and term-born infants, (2) to determine maternal and perinatal factors associated with risk of DD, and (3) to analyze, in LPI, the association between perinatal morbidity and risk of DD.

METHODS

A retrospective cohort study including 163 LPI - 47 cLPI and 116 uLPI - and 158 term-born infants (Terms) was conducted. Parents completed the Ages & Stages Questionnaires®3rd Spanish version (ASQ3). Risk of DD was defined as the presence of any ASQ3 domain scoring below the mean minus 2 SD. Association between risk of DD and maternal and perinatal factors was analysed using a multivariate logistic model. Incidence of risk of DD was analysed according to specific morbidity.

RESULTS

Compared to Terms, cLPI have a higher risk of DD in the communication domain. Respiratory pathology was associated with a higher risk in the communication domain. Caesarean delivery was the only maternal perinatal risk factor for DD, especially in gross motor domain.

CONCLUSIONS

At the age of 4years cLPI, especially those with respiratory morbidity, had a higher risk of communication delay. Caesarean delivery was the only perinatal risk factor associated with risk of DD.

Emotional and behavioral outcomes and quality of life in school-age children born as late preterm: retrospective cohort study

Aim

To determine the effect of late preterm birth and treatment at the intensive care unit (ICU) on school-age children’s emotional and behavioral problems and quality of life (QoL).

Methods

Emotional and behavioral problems and QoL were investigated in 6-12-year-olds who were born late preterm at the University Hospital Center Split in the period from January 2002 to March 2008. The study included 126 late preterm children treated in ICU (LP-ICU group), 127 late preterm children not treated in ICU (LP-non-ICU group), and 131 full-term children treated in ICU (FT-ICU group). Emotional and behavioral difficulties were assessed using the Child Behavior Checklist. QoL was evaluated with the Royal Alexandra Hospital for Children Measure of Function questionnaire. The data was collected via telephone interview with mothers during 2014.

Results

Late preterm children had a nearly 5-fold risk for internalizing problems in comparison with FT-ICU children (OR 4.76, 95% confidence interval [CI] 2.37-9.56 and OR 4.82, 95% CI 2.25-10.37 in LP-ICU and LP-non-ICU children, respectively). They also had a greater risk for externalizing problems (OR 3.08, 95% CI 1.44-6.61 and OR 2.68, 95% CI 1.14-6.28, respectively) and total problems (OR 6.29, 95% CI 2.86-13.83 and OR 7.38, 95% CI 3.08-17.69, respectively) and a considerably increased risk for lower QoL (OR 12.79, 95% CI 5.56-29.41 and OR 5.05, 95% CI 2.04-12.48, respectively).

Conclusion

Children born late preterm had a greater risk for emotional and behavioral problems and lower QoL during childhood than their full-term born peers and they experienced serious health problems upon birth.

Risk Factors for Early Preterm Birth at King Salman Armed Force Hospital in 2010

AIM:

To investigate risk factors for early preterm birth.

METHODS AND MATERIAL:

A retrospective comparative study was conducted at Tabuk, Kingdom of Saudi Arabia during the period from January to December 2010. Five hundred and ninety-five patient’s files and delivery registry logbooks were reviewed, the following information was collected; demographic data, current and past obstetric histories. Then the early and late preterm births were compared for various risk factors. The Statistical Package for Social Sciences (SPSS version 22) was used. The Chi-square and t-test were used to test the statistical significance and a P-value<0.05 considered significant.

RESULTS:

Prevalence of early preterm birth was found to be 2.5% in our study group. Women at risk for early preterm birth were: primigravidas (33.7% vs. 26.2% for control), P-value 0.039, OR 1.429 and 95% CI 0.982 - 2.079); multiple gestations (87.7% vs. 95.1% for control, P-value 0.002, OR 0.368 and 95% CI 0.196 - 0.688); and patients with a prior history of placental abruption (3.7% vs. 1.0% for control, P-value 0.027, OR3.928 and 95% CI 1.1360 - 13.586).

CONCLUSIONS:

Current study indicated that early preterm births differed from preterm as a whole; primigravida, multiple gestations and a history of placental abruption are independent risk factors for them.

Effect of alcohol consumption and psychosocial stressors on preterm and small-for-gestational-age births in HIV-infected women in South Africa: a cohort study

OBJECTIVES

Psychosocial stressors such as depression and stress, intimate partner violence (IPV) and alcohol use have been linked to preterm and small-for-gestational-age (SGA) births in general populations. The prevalence of psychosocial stressors and alcohol abuse is high in many HIV-infected (HIV+) populations. Our objective was to evaluate the effects of psychosocial stressors and alcohol abuse on birth outcomes in HIV-infected women.

METHODS

Antenatal depression and non-specific psychological distress, periconception IPV and alcohol consumption were measured during the second trimester among HIV+ women initiating antiretroviral treatment with efavirenz + emtricitibine + tenofovir in Cape Town, South Africa. Log binomial regression models were used to estimate the risk ratios (RR) and 95% CIs of the effects of psychosocial stressors and periconception alcohol consumption on birth outcomes: SGA (birth weight <10th centile for gestational age) and preterm (<37 weeks) births.

RESULTS

Of the 571 mother-infant pairs, 26% of women reported hazardous alcohol consumption (Alcohol Use Disorders Identification Test-C score ≥3) periconception periods, 11% reported depressive symptoms, 7% reported non-specific psychological distress and 15% reported experiencing physical or psychological IPV. 14% of infants were born preterm and 12% were SGA. Infants born to women reporting hazardous drinking were twice (adjusted RR 2.00 (95% CI 1.13 to 3.54)) as likely to be SGA compared with women reporting low alcohol intake. Alcohol consumption did not have a significant effect on the incidence of preterm birth. Depressive symptoms, non-specific psychological distress, physical and psychological IPV did not increase the risk of SGA or preterm birth significantly.

CONCLUSIONS

The observed elevated risk of SGA births associated with periconception alcohol consumption underscores the urgent need to reduce alcohol consumption among women of childbearing age. Interventions targeting modifiable risk factors of adverse birth outcomes need to be integrated into HIV prevention and maternal child health programmes to improve the long-term health of HIV-exposed children.

TRIAL REGISTRATION NUMBER

NCT01933477; Pre-results.

Outcomes of infants born near term

Most research on outcomes of preterm birth has centred on babies born at <32 weeks gestation and at highest risk of mortality and serious morbidity. Recent years have seen a dramatic increase in studies focusing on late preterm infants (34-36 weeks gestation). Early epidemiological studies demonstrated increased risks of mortality and adverse neonatal outcomes in this group, prompting further investigations. These increased risks have been confirmed and more recent studies have also included babies born at 37-38 weeks, now defined as 'early-term' births. It now seems that it is inappropriate to consider term and preterm as a dichotomy; gestational age rather represents a continuum in which risk and severity of adverse outcomes increase with decreasing gestational age, but where measurable effects can be detected even very close to full term. In this review, we summarise current evidence for the outcomes of infants born at late preterm and early-term gestations.

Risk of developmental delay: Comparison of late preterm and full term Canadian infants at age 12 months

BACKGROUND

Late preterm (34(0/7) to 36(6/7)weeks gestation) infants may experience developmental delays greater than those found in term (≥ 37(0/7)weeks gestation) infants.

AIM

The aim of this study was to compare the risk of developmental delay between late preterm and full-term Canadian born infants at age 12months, and to determine infant and maternal factors associated with risk of delay.

METHODS

A descriptive comparative study was conducted from data available from the All Our Babies community-based, prospective, pregnancy cohort in Calgary, Alberta. Participants were a sample of mothers of 52 infants born late preterm and 156 randomly selected mothers of term infants, matched for infant sex; eligible infants were singleton births. Mothers completed a developmental screening tool, the Ages and Stages Questionnaire, version 3 (ASQ-3), when their infant was age 12months. Corrected age (CA) was used for preterm infants.

RESULTS

Both late preterm and term infants who required neonatal intensive care (NICU) were more likely to demonstrate risk of developmental delay. Compared to term infants, there was a trend for late preterm infants to be at risk of communication and gross motor delay at age 12months CA that was attenuated to the null when adjustments were made for NICU admission and other covariates.

CONCLUSIONS

Infants born between 34 and 41weeks who are admitted to NICU are at increased risk of developmental delay. Early identification of risk provides an opportunity for referral for developmental assessment and early intervention programming.

Developmental outcomes and physical activity behaviour in children post major surgery: an observational study

Background

Infants may be at neurodevelopmental risk from adverse events arising in the neonatal period. This study aimed to investigate the developmental outcomes and physical activity behaviours of term infants after neonatal major surgery, at age three years.

Methods

This prospective study enrolled infants who underwent major surgery in their first 90 days, between August 2006 and December 2008. Developmental status was assessed using the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III). Physical activity and sedentary behaviour (i.e. small screen recreation) (SSR) were assessed using the Preschool-Age Physical Activity Questionnaire (Pre-PAQ). Activity (moving between slow to fast pace) and SSR were reported for a 3-day period.

Results

One hundred and thirty five children (68 major surgery, 67 control) were assessed, using both measures, at age three years. Both groups were within the average range across all domains of the BSID-III although the surgical group was significantly below the controls for cognition (t = −3.162, p = 0.002) receptive language (t = −3.790, p < 0.001) and fine motor skills (t = −2.153, p = 0.03). Mean activity time for the surgical group was 191 mins.day⁻¹, and 185 mins.day-1 for controls. Mean SSR time was 77 mins.day⁻¹, and 83 mins.day⁻¹ for the respective groups. There was no significant difference between groups for either physical activity (p = 0.71) or SSR time (p = 0.49).

Conclusions

By age three, children who had major surgery in infancy are developmentally normal but have not quite caught up with their peer group in cognitive, receptive language and fine motor skill domains. Both groups met recommended 3 h of daily physical activity but exceeded 60-min SSR time recommended for preschool-age children.

Late Preterm Infants and Neurodevelopmental Outcomes at Kindergarten

BACKGROUND AND OBJECTIVE

Late preterm infants (LPIs) (gestation 34 weeks and 0 days to 36 weeks and 6 days) compared with full-term infants (FTIs) are at increased risk for mortality and short- and long-term morbidity. The objective of this study was to assess the neurodevelopmental outcomes in a longitudinal cohort study of LPIs from infancy to school age and determine predictive values of earlier developmental testing compared with school-age testing.

METHODS

We used general estimating equations to calculate the odds of school readiness in a nationally representative cohort of 4900 full-term and 950 late preterm infants. We generated positive and negative predictive values of the ability of the 24-month Mental Developmental Index (MDI) scores of the Bayley Short Form, Research Edition, to predict Total School Readiness Score (TSRS) at kindergarten age.

RESULTS

In multivariable analysis, late preterm infants had higher odds of worse TSRSs (adjusted odds ratio 1.52 [95% confidence interval 1.06-2.18], P = .0215). The positive predictive value of a child having an MDI of <70 at 24 months and a TSRS <5% at kindergarten was 10.4%. The negative predictive value of having an MDI of >70 at 24 months and a TSRS >5% was 96.8%. Most infants improved score ranking over the study interval.

CONCLUSIONS

LPIs continue to be delayed at kindergarten compared with FTIs. The predictive validity of having a TSRS in the bottom 5% given a MDI <70 at 24 months was poor. A child who tested within the normal range (>85) at 24 months had an excellent chance of testing in the normal range at kindergarten.

Gestational age and developmental risk in moderately and late preterm and early term infants

OBJECTIVES

The objective of this study was to evaluate the association between gestational age (GA) at birth and risk of developmental delay at 8 and 18 months of corrected postnatal age.

METHODS

During 2008 to 2011, infants at a corrected postnatal age of 8 or 18 months attending health centers in Santiago, Chile, were recruited. Participants completed a form on biographical and demographic characteristics and the Chilean validated version of the Ages and Stages Questionnaires, Third Edition (ASQ). Logistic regression was used to detect the capacity of GA to predict scores < -2 SDs on the basis of the Chilean ASQ reference group, in at least 1 ASQ domain, adjusted by different control variables.

RESULTS

A total of 1667 infants were included in the analysis. An inverse "dose response" relationship between developmental delay risk and GA at birth was found, both in the crude and adjusted models. Compared with those born full term, the odds ratio for developmental delay risk was 1.56 for those born early term (95% confidence interval [CI]: 1.19-2.06), 2.58 for infants born late preterm (95%CI: 1.66-4.01), and 3.01 for those born moderately preterm (95%CI: 1.59-5.71).

CONCLUSIONS

An inverse dose-response relationship between GA and risk of developmental delay was found in the tested population. Future prospective studies and predictive models are needed to understand whether this higher developmental risk in moderately and late preterm infants is transient and modifiable or persists throughout life, allowing for better targeting of early-intervention strategies.

Parent ratings of child cognition and language compared with Bayley-III in preterm 3-year-olds

BACKGROUND

Parent ratings on questionnaires may provide valid and cost-effective tools for screening cognitive development of children at risk of developmental delay.

AIMS

In this study, we examined the convergent validity of combining parent-based reports of non-verbal cognitive abilities (PARCA3) and verbal abilities (CDI-III) in relation to the Bayley-III cognitive scale in 3-year-olds born late pre-term.

METHODS

Mothers of 185 late-preterm children were asked to complete the PARCA3 and the CDI-III shortly before children reached age three; children were then assessed using the Bayley-III close to their third birthday.

RESULTS

The two maternal questionnaires were significantly and moderately correlated with the Bayley-III cognitive scores. Together the maternal ratings accounted for 15% of the variance in the Bayley-III cognitive scores, after controlling for other covariates in regression analysis. In particular, the PARCA3 contributed significantly to explain variance in the Bayley-III cognitive scores when controlling for the CDI-III. However, the CDI-III was also independently associated with the Bayley-III cognitive scores.

CONCLUSIONS

Parent ratings of child cognition and language together may provide cost-effective screening of development in "at risk" preschoolers.

Behavioural outcomes at 3 years of age among late preterm infants admitted to neonatal intensive care: a cohort study

OBJECTIVE

Examine the behavioural outcomes at age 3 years of late preterm infants (LPIs) who were admitted to neonatal intensive care (NIC) in comparison with LPIs who were not admitted.

METHOD

This cohort study prospectively recruited 225 children born late preterm (34-36(+6) weeks gestation) in 2006 in Northern Ireland, now aged 3 years. Two groups were compared: LPIs who received NIC (study; n=103) and LPIs who did not receive NIC (control; n=122). Parents/guardians completed the Child Behaviour Checklist/1½-5. Descriptive maternal and infant data were also collected.

RESULTS

As expected LPI children admitted to NIC had higher medical risk than the non-admitted comparison group (increased caesarean section, born at earlier gestation, lower birth weight and an episode of resuscitation at birth). LPIs admitted to NIC scored higher on the Child Behaviour Checklist/1½-5 compared with those who were not admitted indicating more behavioural problems; this was statistically significant for the Aggressive Behaviour Subscale (z=-2.36) and the Externalising Problems Scale (z=-2.42). The group difference on the Externalising Problems Scale was no longer significant after controlling for gender, gestational age and deprivation score.

CONCLUSIONS

This study provides valuable data on the behaviour at age 3 years of LPIs admitted to NIC compared with LPIs not admitted to NIC. Further research would be beneficial to explore medical and psychosocial explanations for observed differences between groups using large prospective cohort studies.

Neonatal intensive care and late preterm infants: health and family functioning at three years

BACKGROUND

Late preterm infants (LPIs), born at 34+0 to 36+6 weeks of gestation contribute a significant proportion of all neonatal intensive care (NIC) admissions and are regarded as being at risk of adverse outcomes compared to term-born infants.

AIM

To explore the health outcomes and family functioning of LPIs who required neonatal intensive care, at three years of age.

STUDY DESIGN AND SUBJECTS

This cohort study included 225 children born late preterm, between 1 January and 31 December 2006 in Northern Ireland. Children admitted for NIC (study group, n=103) were compared with children who did not require NIC or who required special care only for up to three days (comparison group, n=122).

OUTCOME MEASURES

Health outcomes were measured using the Health Status Questionnaire, health service usage by parent report and family functioning using the PedsQL™ Family Impact Module.

RESULTS

LPIs who required NIC revealed similar health outcomes at three years in comparison to those who did not. Despite this, more parents of LPIs who required NIC reported visiting their GP and medical specialists during their child's third year of life. Differences in family functioning were also observed with mothers of LPIs who required NIC reporting, significantly lower levels of social and physical functioning, increased difficulties with communication and increased levels of worry.

CONCLUSIONS

LPIs were observed to have similar health outcomes at three years of age regardless of NIC requirement. The increase in GP and medical specialist visits and family functioning difficulties observed among those infants who required NIC merits further investigation.

Late preterm infants: near term but still in a critical developmental time period

Late preterm (LP) infants are defined as those born at 34-0/7 to 36-6/7 weeks' gestational age. LP infants were previously referred to as near term infants. The change in terminology resulted from the understanding that these infants are not fully mature and that the last 6 weeks of gestation represent a critical period of growth and development of the fetal brain and lungs, and of other systems. There is accumulating evidence of higher risks for health complications in these infants, including serious morbidity and a threefold higher infant mortality rate compared with term infants. This information is of critical importance because of its scientific merits and practical implications. However, it warrants a critical and balanced review, given the apparent overall uncomplicated outcome for the majority of LP infants. Others reviewed the characteristics of LP infants that predispose them to a higher risk of morbidity at the neonatal period. This review focuses on the long-term neurodevelopmental and respiratory outcomes, with the main aim to suggest putative prenatal, neonatal, developmental, and environmental causes for these increased morbidities. It demonstrates parallelism in the trajectories of pulmonary and neurologic development and evolution as a model for fetal and neonatal maturation. These may suggest the critical developmental time period as the common pathway that leads to the outcomes. Disruption in this pathway with potential long-term consequences in both systems may occur if the intrauterine milieu is disturbed. Finally, the review addresses the practical implications on perinatal and neonatal care during infancy and childhood.