ARTICLE

Gestational Age, Health, and Educational Outcomes in AdolescentsMary J. Berry, MBBS, PhD, a, b Tim Foster, MBChB, c, d Kate Rowe, MBChB, b Oliver Robertson, MCom, c Bridget Robson, BA, c Nevil Pierse, PhDc

BACKGROUND AND OBJECTIVES: As outcomes for extremely premature infants improve, up-to-date, large-scale studies are needed to provide accurate, contemporary information for clinicians, families, and policy makers. We used nationwide New Zealand data to explore the impact of gestational age on health and educational outcomes through to adolescence.METHODS: We performed a retrospective cohort study of all births in New Zealand appearing in 2 independent national data sets at 23 weeks' gestation or more. We report on 2 separate cohorts: cohort 1, born January 1, 2005 to December 31, 2015 (613 521 individuals), used to study survival and midterm health and educational outcomes; and cohort 2, born January 1, 1998 to December 31, 2000, and surviving to age 15 years (146 169 individuals), used to study high school educational outcomes. Outcomes described by gestational age include survival, hospitalization rates, national well-being assessment outcomes at age 4 years, rates of special education support needs in primary school, and national high school examination results.RESULTS: Ten-year survival increased with gestational age from 66% at 23 to 24 weeks to >99% at term. All outcomes measured were strongly related to gestational age. However, most extremely preterm children did not require special educational support and were able to sit for their national high school examinations.CONCLUSIONS: Within a publicly funded health system, high-quality survival is achievable for most infants born at periviable gestations. Outcomes show improvement with gestational ages to term. Outcomes at early-term gestation are poorer than for children born at full term.

abstract

Departments of aPaediatrics and Child Health and cPublic Health, University of Otago, Wellington, Wellington, New Zealand; bCapital and Coast District Health Board, Wellington, New Zealand; and dHawke’s Bay District Health Board, Napier, New Zealand

Dr Berry conceptualized and designed the study, drafted the manuscript, and was responsible for the clinical interpretation of the study data and overall supervision of the research project; Drs Foster and Pierse conceptualized and designed the study, designed the statistical analyses, accessed the study data through Statistics New Zealand’s Integrated Data Infrastructure, and conducted the statistical analyses; Dr Rowe assisted in drafting the manuscript and was responsible for the clinical interpretation of the study data; Mr Robertson accessed the study data through Statistics New Zealand’s Integrated Data Infrastructure and assisted in conducting the statistical analyses; Ms Robson conceptualized and designed the study and assisted in data interpretation; and all authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.

The results in this article are not official statistics. They have been created for research purposes from the Integrated Data Infrastructure (IDI), managed by Statistics New Zealand. The opinions, findings, recommendations, and conclusions expressed in this article are those of the authors, not Statistics New Zealand. Access to the anonymized data used in this study was provided by Statistics New Zealand under the security and confidentiality provisions of the Statistics Act 1975. Only people authorized under the Statistics Act 1975 are allowed to see data about a particular

PEDIATRICS Volume 142, number 5, November 2018:e20181016

WHAT’S KNOWN ON THIS SUBJECT: Gestational age is known to influence rates of neonatal survival as well as longer-term neurodevelopmental and educational outcomes. However, most long-term outcome data reflect selected cohorts or predate recent advances in neonatal care.

WHAT THIS STUDY ADDS: We show that gestational age <39 weeks is associated with increased rates of hospitalization, developmental concerns, and educational challenges through to adolescence. However, even extremely preterm infants have high survival rates and can do well academically.

To cite: Berry MJ, Foster T, Rowe K, et al. Gestational Age, Health, and Educational Outcomes in Adolescents. Pediatrics. 2018;142(5):e20181016

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Advances in perinatal medicine over the last 20 years have dramatically improved survival for preterm infants.1 With increasing survival, 2 – 7 we urgently need more information about the long-term impact of preterm birth.

One of the most challenging areas of perinatal medicine is the care of periviable infants (defined here as gestation <25 weeks and/or birth weight <500 g). Recommendations around intervention and resuscitation at the threshold of viability vary greatly.8 In this context, there is a need for accurate, contemporary information used to describe long-term and short-term outcomes.9

Researchers in large cohort studies such as EPICure, EPIPAGE, the Extremely Preterm Infants Study in Sweden, and Extremely Preterm Infants in Belgium describe the morbidity and mortality experienced by extremely preterm infants.2, 10 – 14 It is clear that preterm birth increases the rate of hospital readmissions15 and affects behavior and academic performance at school16 – 19 in both very preterm20 – 24 and late-preterm infants.25 – 27 Others have reported longer-term gestational age–associated health, 28, 29 social, 30 and educational17 outcomes from cohorts born in the 1970s and 1980s. However, the generalizability of their findings is limited because perinatal care of the era was different from contemporary practice.

Additionally, those within the moderate- and late-preterm group are still at increased risk of adverse health, educational, and social outcomes, 31 –35 and birth at early term (37–38 weeks’ gestation) is associated with poorer elementary school–level educational outcomes, 36 but the longer-term impact is unknown. In an era when the timing of birth near term may arise from social factors rather than medical indications, 37, 38 the full impact of these choices must be understood

to allow for robust parental participation in decision-making.

Taken together, there is evidence that gestational age is an important mediator of later adversity. However, the strength of this relationship is unclear because of varied population selection, methodologies, sample sizes, and end points.20 There is a need to provide a national, holistic overview of the impact of gestational age, from periviable to postterm, on well-being across all aspects of an individual’s life.

The New Zealand Government has recently made a unique data resource available.39 The Integrated Data Infrastructure (IDI) is a comprehensive collection of central data sets containing deidentified health, education, and social data linked at an individual level. It contains information about all births and deaths, all hospital admissions (coded by International Classification of Diseases, 10th Revision [ICD-10] classification), a national health and well-being screening assessment (Before School Checks [B4SCs]), and information on educational outcomes, such as primary school interventions and high school examinations. Using the IDI, the impact of gestational age can be quantified on a national basis to provide a unique, comprehensive assessment of well-being across multiple domains.

METHODS

Integrated Data Infrastructure

All data used in this study were deidentified New Zealand governmental data linked at an individual level. The data were collected, linked, and deidentified by Statistics New Zealand and made available through the IDI.

Ethics

The University of Otago Ethics Committee provided institutional approval (HD16/053). Confidentiality approval was obtained from Statistics New Zealand to access the IDI.

Confidentiality

In accordance with the Statistics Act 1975 and Statistics New Zealand’s confidentiality rules, all data are in compliance with standard government confidentiality standards. Briefly, raw counts are random rounded to base 3, raw counts <6 are not reported, and means are only reported if they are based on >20 individuals (see Statistics New Zealand’s Microdata Output Guide 40).

Population Ascertainment

Study inclusion required linked birth records from 2 sources: the Department of Internal Affairs (DIA) and the Ministry of Health’s (MoH) National Minimum Dataset (NMD). All births from 23 + 0/7 weeks’ gestation identified in the DIA were matched to live births identified in the NMD over the same period. Matching across data sets was made possible by using the IDI spine.40 Individuals were included if they were present in both data sets and if their gestational ages matched between the 2 records, indicating that included children were live born and linkable within the IDI (∼95% of individuals within this age range are linkable with <1% error in the linking methodology).41, 42 Gestational ages for all infants were based on weeks’ completed gestation as ascertained by the obstetric care provider.

Individuals were excluded if there was no subsequent record of death, hospitalization, any prescription receipt, B4SC, or school attendance.

Two different cohorts were identified. Epoch 1 included all live births of ≥23 weeks’ gestation in New Zealand between 2005 and 2015. This was done to provide a cohort of children who would have completed their B4SCs at age 4 years and have primary school data available in the IDI (the B4SC program was introduced in 2008, and primary school data

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are available in the IDI from 2007 onward). This cohort was used to study short midterm outcomes (survival, childhood hospitalization, developmental screening, and primary school). Epoch 2 included all live births of ≥23 weeks’ gestation in New Zealand between 1998 and 2000 and surviving to the age of 15 years. This epoch was chosen to provide a cohort of children who will have completed their National Certificate of Educational Achievement (NCEA) Level 1 examinations and sat nationwide at the age of 15 years but were born from 1998 onward (when gestational age became reported compulsorily as part of birth data). We used this cohort to study long-term educational achievement.

Age, sex, and ethnicity data were derived from birth records. Socioeconomic status was based on each child’s birth address by using the New Zealand Index of Deprivation (NZDep). The NZDep is a small area-based measure of social deprivation; areas with the lowest levels of deprivation have a score of 1, and areas with the highest deprivation have a score of 5.43

Data Collection

Primary outcome measures were mortality, number and causes of hospi-talization from birth to age 10 years, developmental or behavioral problems at age 4 years, school enrollment and need for additional learning support,

and NCEA achievement (see the Education subsection).

Outcome Measures

All outcome measures are described for gestational age increments from periviable (23–24 weeks) through to early term (37–38 weeks) relative to our full-term reference control group (39–40 weeks). Because some infants were either not old enough at the end of the study period to complete the cross-sectional assessments (eg, NCEA) or had died before completing them, all study participants are not included in those measures.

Survival

Survival estimates for live-born infants were calculated to 10 years of age. Because of the complex ethics around the initiation (or noninitiation) of NICU intervention for infants born at <25 weeks’ gestation, survival rates were derived from live-born infants to whom resuscitation was offered instead of live-born infants who had no record of a resuscitation attempt. MoH birth records reveal whether a newborn infant received mechanical ventilation, noninvasive ventilation, or continuous positive airway pressure. The resuscitation of periviable infants inevitably involves 1 of these methods.8 Thus, resuscitation was assumed not to have been initiated in infants born at <25 weeks’ gestation who died in the first 48 hours of life without any record of mechanical ventilation, noninvasive ventilation, or

continuous positive airway pressure. These infants were excluded from survival analyses. For infants of <31 weeks’ gestation, survival was also analyzed by birth weight.

Hospitalization

Hospitalization data were analyzed from the time of first discharge from the hospital until 10 years of age by using the NMD. This included inpatient admissions but excluded emergency department presentations because these are coded separately from the NMD and are not available for the whole study period. Transfers between wards or hospitals were counted as a single admission and are coded differently from new readmissions by the MoH. The principal diagnosis was obtained from the ICD-10 code (used consistently for the 2005–2015 period) at time of discharge from the hospital, which is available as part of routine data reported to MoH.

B4SC

The B4SC is a universal health and well-being screening assessment that has been available to all 4-year-old children in New Zealand since 2008. The B4SC provides a robust national audit of children’s well-being.44 Aspects of the B4SC included in this study include (1) anthropometric growth data, (2) the Strengths and Difficulties Questionnaire (completed by parents45 and [if

PEDIATRICS Volume 142, number 5, November 2018 3

TABLE 1 Demographic Summary of Study Cohort

Gestation, wk

Ethnicity Female Sex

NZDep Quintile Total

Māori Pacific Islander

European and/or Other

1 (Least Deprived)

2 3 4 5 (Most Deprived)

Missing

23–24 150 84 315 252 81 75 78 126 159 30 54925–26 264 147 546 456 144 150 165 213 249 36 95727–28 357 183 831 615 195 192 267 300 342 75 137129–30 522 252 1428 999 336 351 438 447 510 120 220231–32 906 417 2586 1779 537 690 738 873 903 168 390933–34 2037 921 6246 4149 1485 1524 1869 1962 1944 420 920435–36 5619 2721 17 571 12 096 4116 4257 5013 5499 5751 1275 25 91137–38 27 525 15 525 88 899 62 346 21 018 21 876 25 347 28 242 28 854 6612 131 94939–40 70 410 39 873 218 997 162 159 51 765 55 266 62 688 70 869 72 813 15 879 329 28041+ 21 381 12 219 74 589 53 055 16 692 18 123 21 495 23 379 22 950 5550 108 189Total 129 300 72 435 411 786 298 116 96 414 102 558 118 197 131 991 134 622 29 739 613 521

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BERRY et al4

FIGURE 1Overall survival and survival of periviable infants. A, Survival of resuscitated live-born infants to age 10 years. B, Survival of resuscitated infants of 23 weeks’ gestation to age 2 years. C, Survival of resuscitated infants of 24 weeks’ gestation to age 2 years. D, Survival of resuscitated live-born infants by birth weight and gestation.

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available] early-childhood educators), and (3) the Parents’ Evaluation of Developmental Status (PEDS) questionnaire. The mean scores for each gestational week group were calculated for prosocial behaviors, hyperactivity, conduct and emotional difficulties, and PEDS questionnaire results. The PEDS questionnaire is a developmental surveillance tool with a sensitivity of 74% to 79% and a specificity of 70% to 80% for clinically relevant developmental problems.44 The PEDS scores with 1 or more areas of concern were compared with those with no or nonsignificant concerns for each gestational week group.

Education

The IDI captures elementary school data from 2007 onward. Children are required to be enrolled in primary

school in New Zealand by age 6 years. These data exclude the 0.8% of children in New Zealand who are homeschooled.46 Children with additional learning needs receive support through the Resource Teachers: Learning and Behaviour (RTLB) service. The Reading Recovery program is an early literacy intervention used to target children who are falling behind after 1 year at school.47 We calculated the rates of primary school, RTLB service, and Reading Recovery enrollment for each gestational week group.

In New Zealand, the first formal educational qualification, NCEA Level 1, is achieved in year 11 of secondary school (US equivalent: grade 10), normally at 15 to 16 years of age. We report findings from Epoch 2 (children born 1998–2000) and

describe percentiles on the basis of weighted NCEA results compiled by the Ministry of Education.

Statistical Analyses

Raw survival was described by using Kaplan-Meier estimates (with the Greenwood formula used to estimate variance). The logrank test was used to test differences in Kaplan-Meier estimates. Hazard ratios for the effect of covariates were calculated by using a Cox proportional hazards model.

For the effect of birth weight on outcomes of interest, spline smoothing was used to model the relationship as a nonlinear smooth function. The smoothing parameter was chosen by using generalized cross-validation, and confidence limits were calculated nonparametrically by using the bootstrap. The bootstrap was also used to estimate the variance in mean hospitalization rates. Otherwise, standard statistical methods and tests were used.

All statistical analyses and data handling were performed in R.48 Survival analyses were performed by using R’s survival package, and standard bootstrap methods were performed by using the boot package; otherwise, all analyses were performed by using the base or stats packages and the authors’ own code.

Unless otherwise specified, gestational age was divided into

PEDIATRICS Volume 142, number 5, November 2018 5

TABLE 2 Hospitalization Rate per 10 000 Child-Years by Gestation and Chronological Age

Gestation, wk Age, y

<1 1–5 6–9

23–24 23 986** 8486** 1955**

25–26 19 672** 6321** 1991**

27–28 16 180** 4427** 1543**

29–30 11 563** 3551** 1473**

31–32 9280** 2826** 1336**

33–34 6830** 2369** 1005**

35–36 5662** 2011** 946**

37–38 4241** 1675** 841**

39–40 3358a 1492a 752a

41+ 3057** 1435** 744

Children born preterm were more likely to be admitted for a respiratory illness than for other reasons (Table 3), with 46% of the admissions being of periviable infants for respiratory conditions (giving a 14 times higher risk of admission due to respiratory illness than for children born at full term). P values are versus those born at 39 to 40 wk.a Reference.** P < .01.

TABLE 3 Admission Cause Based on Primary Diagnosis

GA Infection (Nonrespiratory and/

or GI

Injury, % EENT, % Perinatal, a % Congenital, % Respiratory, % Gastroenterological, %

Other, %

23–24 6 7 10 6 3 46 5 1625–26 6 9 9 5 4 40 7 2027–28 8 8 9 7 5 37 7 1929–30 7 9 10 6 4 35 9 1931–32 8 9 9 5 6 32 9 2233–34 10 11 9 4 5 28 9 2435–36 10 13 7 5 6 26 9 2437–38 11 15 7 4 5 24 8 2639–40 11 16 8 3 4 24 8 2641+ 10 17 8 2 4 23 9 26

EENT, eye, ear, nose, and throat; GA, gestational age; GI, gastroenterological.a Perinatal refers to a heterogeneous group of conditions grouped within ICD-10 chapter 17, “certain conditions originating in the perinatal period.”

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BERRY et al6

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2-week epochs from 23 + 0/7 to 24 + 6/7 weeks’ gestation through to ≥41 + 0/7 weeks’ gestation. All error bars or bands for graphs are used to display the 95% confidence interval unless otherwise stated.

RESULTS

Epoch 1

Participants

The DIA identified 678 072 live births at ≥23 weeks’ gestation between January 1, 2005, and December 31, 2015. After exclusions due to infants not having matching NMD records and loss to follow-up, we report outcomes for 613 521 eligible individuals.

The demographic characteristics of infants included in the study are reported in Table 1. The preterm birth rate (<37 + 0/7 weeks) was 7.2%. Periviable infants (<25 + 0/7 weeks) accounted for 0.09% (n = 549) of all births.

Families in high–social deprivation areas (measured by deprivation quintile) made up a higher proportion of all live births and are overrepresented at gestations <30 weeks and among those delivering postterm (Table 1).

Survival

In Fig 1A, we show survival to 10 years (with 95% confidence bands for individually drawn survival curves). At all gestational ages, the greatest risk of mortality was in the neonatal period, plateauing after the first year of age.

Among infants born at <25 weeks (n = 549), 396 were actively resuscitated. This included 87 of 201 infants of 23 weeks’ gestation and 312 of 348 infants of 24 weeks’ gestation.

With increasing gestational age, there was a statistically significant increase in survival for each gestation week group through to term (Supplemental Table 7).

Over time, the survival rates for each gestational age improved, with relative hazard of death decreasing by 2.5% for each year (hazard ratio = 0.975; P < .001; Supplemental Table 7) and no significant interaction by gestational age over the 10 years of the cohort study.

The 10-year survival rates of periviable infants who were presumed to have been actively resuscitated at birth (versus those who were live born and presumed not to have received newborn resuscitation) were 51.2% at 23 completed weeks and 67.6% at 24 completed weeks’ gestation (Figs 1B and 1C).

Figure 1D reveals the estimated effect of birth weight on the survival of infants born at <31 completed weeks’ gestation. With increasing gestational age, the effect of birth weight on survival diminished. Interestingly, survival probability seemingly plateaued for extremely large (>800 g) infants of 23 to 24 weeks’ gestation, which could, for example, represent the deleterious effects of factors that cause a “relative macrosomia” for this gestational age (eg, maternal gestational diabetes). However, the rarity of extremely large infants of 23 to 24 weeks’ gestation creates uncertainty in the estimate outside the range of 500 to 800 g, and further investigation of this effect is needed (Supplemental Fig 3).

Hospitalization

Those of all gestational ages <39 weeks (including early-term infants) had significantly increased rates of hospital admission compared with those born at 39 and 40 weeks’ gestation (Table 2). Overall admission rates were highest in preschool years, but the effect of gestational age persisted to age 10 years.

B4SC

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PEDIATRICS Volume 142, number 5, November 2018 7

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4 years of follow-up (ie, available for B4SC assessment) are shown in Table 4 (87% of available infants were able to be assessed in the B4SC, with loss to assessment not being significantly different across gestational groupings).

The Strengths and Difficulties Questionnaire–Parent and PEDS assessment of developmental concerns

revealed a similar dose response across the gestational age spectrum. From the Strengths and Difficulties Questionnaire–Parent, the lower the gestational ages, the higher the scores for hyperactivity but the lower the score for prosocial behaviors.

Importantly, despite reservations about the long-term outlook for

children born at extremes of gestational age, when using the PEDS assessment, 51% of parents of children born at 23 to 24 weeks’ gestation reported minimal concern about their children’s development.

Gestational age had a statistically, but not biologically, significant impact on growth (Table 4).

BERRY et al8

FIGURE 2NCEA performance by gestational age. A, Proportion of children born between 1998 and 2000 with at least 15 years of follow-up who attempt the NCEA. B, Differences in NCEA performance (percentile differences) by gestational age (reference group is 39–40 weeks’ gestation).

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Education

More than 99% of children with ≥6 years of follow-up data were enrolled in primary school, with no significant differences by gestational age being observed. More than 70% of extremely preterm infants did not have RTLB service or Reading Recovery support.

Epoch 2: NCEA Level 1 Results

Figure 2A reveals the proportion of surviving 15-year-olds for whom NCEA marks were recorded (with the corresponding numbers in Supplemental Table 6), and Fig 2B reveals the average performance. Because the NCEA is the only nationwide high school educational standard recorded in the IDI, no educational data are available for the minority of children who do not have NCEA marks recorded.

Decreasing gestational age was associated with a decrease in the number of adolescents taking the NCEA Level 1 examination as well as a reduction in their NCEA percentiles (which is an estimated ranking produced by the Ministry of Education based on NCEA performance; Fig 2). However, the effect size was small, suggesting that individual variation is much more important when explaining differences in educational achievement (normalized effect size 0.26). Because of the smaller numbers of very premature infants in the cohort born between 1998 and 2000, those born at ≤28 weeks’ gestation were grouped together to provide a precise estimate of percentile performance.

DISCUSSION

Across New Zealand, the resuscitation of periviable infants varies among centers, but the majority of those for whom resuscitation was initiated survived. The factors influencing different resuscitation rates among centers within and outside of New

Zealand are complex8, 49 and cannot be addressed in the current study. Our survival data compare favorably with the international literature, with higher 1-year survival rates than many European and North American centers.50, 51 Because gestational age in New Zealand is almost invariably confirmed by using early–first-trimester ultrasound scanning, high survival rates are unlikely to reflect an inappropriate attribution of a more mature gestational age. Among the survivors, although there is clearly a gestational age effect that persists at least until adolescence, the magnitude of the difference diminishes with age. Additionally, our data consistently reveal that early-term birth is associated with poorer survival, health, educational, and social outcomes.

This study highlights the persistent association between gestations <39 weeks and an increased rate of hospital readmissions, especially for respiratory infection. The additional impact of environmentally modifiable factors (such as adequacy of housing stock)52 on those born preterm needs investigation. Targeted health and social policies may have a role to play in reducing the preterm-associated health disparity.Educational outcomes are reassuring even for periviable infants. Although on a population basis there are preterm-associated deficits, children can perform well at both the primary and high school levels. However, thresholds for specialist educational intervention vary internationally, making meaningful comparisons challenging.24 The majority of those born extremely preterm will attempt the NCEA, and although there is a detectable detrimental effect of any gestational age <39 weeks, prematurity is not incompatible with educational achievement. However, those children who do not attempt the NCEA probably include those with the highest burden of long-term morbidity.

Limitations of the study include the number excluded due to a lack of matching records between the DIA and NMD or loss to follow-up (10% of the possible cohort). Additionally, although the B4SC and NCEA are not mandatory, the majority of children did participate. Finally, some important exposures, such as maternal corticosteroid administration, are not available. However, within New Zealand, almost all mothers in preterm labor from 23 + 0/7 weeks’ gestation will receive at least a partial course of corticosteroids.53

The major strengths of this study are its size, breadth, and use of prospectively recorded whole-population data to get an overview across the full range of gestational ages by using standardized, nationwide outcome measures. The mechanistic basis underpinning these late effects remains to be established.

ACKNOWLEDGMENTS

We acknowledge those at Statistics New Zealand (Tatauranga Aotearoa) for their assistance in accessing and using the IDI.

PEDIATRICS Volume 142, number 5, November 2018 9

ABBREVIATIONS

B4SC:  Before School CheckDIA:  Department of Internal

AffairsICD-10:  International

Classification of Diseases, 10th Revision

IDI:  Integrated Data Infrastructure

MoH:  Ministry of HealthNCEA:  National Certificate of

Educational AchievementNMD:  National Minimum DatasetNZDep:  New Zealand Index of

DeprivationPEDS:  Parents’ Evaluation of

Developmental StatusRTLB, Resource Teachers:  Learning and

Behaviour

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BERRY et al10

person, household, business, or organization, and the results in this article have been made confidential to protect these groups from identification and to keep their data safe. Careful consideration has been given to the privacy, security, and confidentiality issues associated with using administrative and survey data in the IDI. Further detail can be found in the privacy impact assessment for the IDI, available at www. stats. govt. nz.

DOI: https:// doi. org/ 10. 1542/ peds. 2018- 1016

Accepted for publication Aug 14, 2018

Address correspondence to Mary J. Berry, MBBS, PhD, University of Otago, Wellington, PO Box 7343, Wellington 6242, New Zealand. E-mail: max.berry@otago.ac.nz

PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275).

Copyright © 2018 by the American Academy of Pediatrics

FINANCIAL DISCLOSURE: The authors have indicated they have no financial relationships relevant to this article to disclose.

FUNDING: Funding provided by Cure Kids, New Zealand. The funding body had no input into the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the article; or decision to submit the article for publication.

POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose.

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DOI: 10.1542/peds.2018-1016 originally published online October 31, 2018; 2018;142;Pediatrics 

PierseMary J. Berry, Tim Foster, Kate Rowe, Oliver Robertson, Bridget Robson and Nevil

Gestational Age, Health, and Educational Outcomes in Adolescents

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PierseMary J. Berry, Tim Foster, Kate Rowe, Oliver Robertson, Bridget Robson and Nevil

Gestational Age, Health, and Educational Outcomes in Adolescents

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