Short Term Coping-Behaviors and Postpartum Health in a Population-Based Study of Women with a Live Birth, Stillbirth, or Neonatal Death

OBJECTIVE

Responding to the National Institutes of Health Working Group's call for research on the psychological impact of stillbirth, we compared coping-related behaviors by outcome of an index birth (surviving live birth or perinatal loss - stillbirth or neonatal death) and, among individuals with loss, characterized coping strategies and their association with depressive symptoms 6-36 months postpartum.

METHODS

We used data from the Stillbirth Collaborative Research Network follow-up study (2006-2008) of 285 individuals who experienced a stillbirth, 691 a livebirth, and 49 a neonatal death. We conducted a thematic analysis of coping strategies individuals recommended following their loss. We fit logistic regression models, accounting for sampling and inverse probability of follow-up weights to estimate associations between pregnancy outcomes and coping-related behaviors and, separately, coping strategies and probable depression (Edinburgh Postnatal Depression Scale > 12) for those with loss.

RESULTS

Compared to those with a surviving live birth and adjusting for pre-pregnancy drinking and smoking, history of stillbirth, and age, individuals who experienced a loss were more likely to report increased drinking or smoking in the two months postpartum (adjusted OR: 2.7, 95% CI = 1.4-5.4). Those who smoked or drank more had greater odds of probable depression at 6 to 36 months postpartum (adjusted OR 6.4, 95% CI = 2.5-16.4). Among those with loss, recommended coping strategies commonly included communication, support groups, memorializing the loss, and spirituality.

DISCUSSION

Access to a variety of evidence-based and culturally-appropriate positive coping strategies may help individuals experiencing perinatal loss avoid adverse health consequences.

DLK1: A Novel Biomarker of Placental Insufficiency in Stillbirth and Live Birth

OBJECTIVE

 Delta-like homolog 1 (DLK1) is a growth factor that is reduced in maternal sera in pregnancies with small for gestational age neonates. We sought to determine if DLK1 is associated with stillbirth (SB), with and without placental insufficiency.

STUDY DESIGN

 A nested case-control study was performed using maternal sera from a multicenter case-control study of SB and live birth (LB). SB and LB were stratified as placental insufficiency cases (small for gestational age <5% or circulatory lesions on placental histopathology) or normal placenta controls (appropriate for gestational age and no circulatory lesions). Enzyme-linked immunosorbent assay (ELISA) was used to measure DLK1. The mean difference in DLK1 was compared on the log scale in an adjusted linear regression model with pairwise differences, stratified by term/preterm deliveries among DLK1 results in the quantifiable range. In exploratory analysis, geometric means were compared among all data and the proportion of "low DLK1" (less than the median value for gestational age) was compared between groups and modeled using linear and logistic regression, respectively.

RESULTS

 Overall, 234 SB and 234 LB were analyzed; 246 DLK1 values were quantifiable within the standard curve. Pairwise comparisons of case and control DLK1 geometric means showed no significant differences between groups. In exploratory analysis of all data, adjusted analysis revealed a significant difference for the LB comparison only (SB: 71.9 vs. 99.1 pg/mL, p = 0.097; LB: 37.6 vs. 98.1 pg/mL, p = 0.005). In exploratory analysis of "low DLK1," there was a significant difference between the odds ratio of having "low DLK1" between preterm cases and controls for both SB and LB. There were no significant differences in geometric means nor "low DLK1" between SB and LB.

CONCLUSION

 In exploratory analysis, more placental insufficiency cases in preterm SB and LB had "low DLK1." However, low DLK1 levels were not associated with SB.

KEY POINTS

· Maternally circulating DLK1 is correlated with placental insufficiency.. · Maternally circulating DLK1 is not correlated with SB.. · DLK1 is a promising marker for placental insufficiency..

Neurodevelopmental Outcomes of Extremely Preterm Infants Fed Donor Milk or Preterm Infant Formula: A Randomized Clinical Trial

Importance

Maternal milk feeding of extremely preterm infants during the birth hospitalization has been associated with better neurodevelopmental outcomes compared with preterm formula. For infants receiving no or minimal maternal milk, it is unknown whether donor human milk conveys similar neurodevelopmental advantages vs preterm formula.

Objective

To determine if nutrient-fortified, pasteurized donor human milk improves neurodevelopmental outcomes at 22 to 26 months' corrected age compared with preterm infant formula among extremely preterm infants who received minimal maternal milk.

Design, Setting, and Participants

Double-blind, randomized clinical trial conducted at 15 US academic medical centers within the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Infants younger than 29 weeks 0 days' gestation or with a birth weight of less than 1000 g were enrolled between September 2012 and March 2019.

Intervention

Preterm formula or donor human milk feeding from randomization to 120 days of age, death, or hospital discharge.

Main Outcomes and Measures

The primary outcome was the Bayley Scales of Infant and Toddler Development (BSID) cognitive score measured at 22 to 26 months' corrected age; a score of 54 (score range, 54-155; a score of ≥85 indicates no neurodevelopmental delay) was assigned to infants who died between randomization and 22 to 26 months' corrected age. The 24 secondary outcomes included BSID language and motor scores, in-hospital growth, necrotizing enterocolitis, and death.

Results

Of 1965 eligible infants, 483 were randomized (239 in the donor milk group and 244 in the preterm formula group); the median gestational age was 26 weeks (IQR, 25-27 weeks), the median birth weight was 840 g (IQR, 676-986 g), and 52% were female. The birthing parent's race was self-reported as Black for 52% (247/478), White for 43% (206/478), and other for 5% (25/478). There were 54 infants who died prior to follow-up; 88% (376/429) of survivors were assessed at 22 to 26 months' corrected age. The adjusted mean BSID cognitive score was 80.7 (SD, 17.4) for the donor milk group vs 81.1 (SD, 16.7) for the preterm formula group (adjusted mean difference, -0.77 [95% CI, -3.93 to 2.39], which was not significant); the adjusted mean BSID language and motor scores also did not differ. Mortality (death prior to follow-up) was 13% (29/231) in the donor milk group vs 11% (25/233) in the preterm formula group (adjusted risk difference, -1% [95% CI, -4% to 2%]). Necrotizing enterocolitis occurred in 4.2% of infants (10/239) in the donor milk group vs 9.0% of infants (22/244) in the preterm formula group (adjusted risk difference, -5% [95% CI, -9% to -2%]). Weight gain was slower in the donor milk group (22.3 g/kg/d [95% CI, 21.3 to 23.3 g/kg/d]) compared with the preterm formula group (24.6 g/kg/d [95% CI, 23.6 to 25.6 g/kg/d]).

Conclusions and Relevance

Among extremely preterm neonates fed minimal maternal milk, neurodevelopmental outcomes at 22 to 26 months' corrected age did not differ between infants fed donor milk or preterm formula.

Trial Registration

ClinicalTrials.gov Identifier: NCT01534481.

Protocol for the development of a core outcome set for neonatal sepsis (NESCOS)

Neonatal sepsis is a serious public health problem; however, there is substantial heterogeneity in the outcomes measured and reported in research evaluating the effectiveness of the treatments. Therefore, we aim to develop a Core Outcome Set (COS) for studies evaluating the effectiveness of treatments for neonatal sepsis. Since a systematic review of key outcomes from randomised trials of therapeutic interventions in neonatal sepsis was published recently, we will complement this with a qualitative systematic review of the key outcomes of neonatal sepsis identified by parents, other family members, parent representatives, healthcare providers, policymakers, and researchers. We will interpret the outcomes of both studies using a previously established framework. Stakeholders across three different groups i.e., (1) researchers, (2) healthcare providers, and (3) patients' parents/family members and parent representatives will rate the importance of the outcomes in an online Real-Time Delphi Survey. Afterwards, consensus meetings will be held to agree on the final COS through online discussions with key stakeholders. This COS is expected to minimize outcome heterogeneity in measurements and publications, improve comparability and synthesis, and decrease research waste.

Use of term reference infants in assessing the developmental outcome of extremely preterm infants: lessons learned in a multicenter study

OBJECTIVE

Extremely preterm (EP) impairment rates are likely underestimated using the Bayley III norm-based thresholds scores and may be better assessed relative to concurrent healthy term reference (TR) infants born in the same hospital.

STUDY DESIGN

Blinded, certified examiners in the Neonatal Research Network (NRN) evaluated EP survivors and a sample of healthy TR infants recruited near the 2-year assessment age.

RESULTS

We assessed 1452 EP infants and 183 TR infants. TR-based thresholds showed higher overall EP impairment than Bayley norm-based thresholds (O.R. = 1.86; [95% CI 1.56-2.23], especially for severe impairment (36% vs. 24%; p ≤ 0.001). Difficulty recruiting TR patients at 2 years extended the study by 14 months and affected their demographics.

CONCLUSION

Impairment rates among EP infants appear to be substantially underestimated from Bayley III norms. These rates may be best assessed by comparison with healthy term infants followed with minimal attrition from birth in the same centers.

CLINICALTRIALS

GOV ID

Term Reference (under the Generic Database Study): NCT00063063.

Generalizability of the Necrotizing Enterocolitis Surgery Trial to the Target Population of Eligible Infants

OBJECTIVE

The objective of this study was to evaluate whether infants randomized in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network Necrotizing Enterocolitis Surgery Trial differed from eligible infants and whether differences affected the generalizability of trial results.

STUDY DESIGN

Secondary analysis of infants enrolled in Necrotizing Enterocolitis Surgery Trial (born 2010-2017, with follow-up through 2019) at 20 US academic medical centers and an observational data set of eligible infants through 2013. Infants born ≤1000 g and diagnosed with necrotizing enterocolitis or spontaneous intestinal perforation requiring surgical intervention at ≤8 weeks were eligible. The target population included trial-eligible infants (randomized and nonrandomized) born during the first half of the study with available detailed preoperative data. Using model-based weighting methods, we estimated the effect of initial laparotomy vs peritoneal drain had the target population been randomized.

RESULTS

The trial included 308 randomized infants. The target population included 382 (156 randomized and 226 eligible, non-randomized) infants. Compared with the target population, fewer randomized infants had necrotizing enterocolitis (31% vs 47%) or died before discharge (27% vs 41%). However, incidence of the primary composite outcome, death or neurodevelopmental impairment, was similar (69% vs 72%). Effect estimates for initial laparotomy vs drain weighted to the target population were largely unchanged from the original trial after accounting for preoperative diagnosis of necrotizing enterocolitis (adjusted relative risk [95% CI]: 0.85 [0.71-1.03] in target population vs 0.81 [0.64-1.04] in trial) or spontaneous intestinal perforation (1.02 [0.79-1.30] vs 1.11 [0.95-1.31]).

CONCLUSION

Despite differences between randomized and eligible infants, estimated treatment effects in the trial and target population were similar, supporting the generalizability of trial results.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT01029353.

Trends and Racial and Geographic Differences in Infant Mortality in the United States Due to Necrotizing Enterocolitis, 1999 to 2020

This cohort study analyzes yearly trends in necrotizing enterocolitis–related infant mortality rates (NEC-IMR) from 1999 to 2020, overall and by Black and White race, and described Black-to-White NEC-IMR ratios and NEC-IMR for US states.

Incidence of and Neurodevelopmental Outcomes After Late-Onset Meningitis Among Children Born Extremely Preterm

Importance

Late-onset meningitis (LOM) has been associated with adverse neurodevelopmental outcomes in children born extremely preterm.

Objective

To report the incidence of LOM during birth hospitalization and neurodevelopmental outcomes at 18 to 26 months' corrected age.

Design, Setting, and Participants

This cohort study is a secondary analysis of a multicenter prospective cohort of children born at 22 to 26 weeks' gestation between 2003 and 2017 with follow-up from 2004 to 2021. The study was conducted at 25 Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network centers.

Exposures

Culture-confirmed LOM.

Main Outcomes and Measures

Incidence and microbiology of LOM (2003-2017); lumbar puncture (LP) performance in late-onset sepsis (LOS) evaluations (2011-2017); composite outcome of death or neurodevelopmental impairment (NDI; 2004-2021).

Results

Among 13 372 infants (median [IQR] gestational age, 25.4 [24.4-26.1] weeks; 6864 [51%] boys), LOM was diagnosed in 167 (1%); LOS without LOM in 4564 (34%); and neither LOS nor LOM in 8641 (65%). The observed incidence of LOM decreased from 2% (95% CI, 1%-3%) in 2003 to 0.4% (95% CI, 0.7%-1.0%) in 2017 (P < .001). LP performance in LOS evaluations decreased from 36% (95% CI, 33%-40%) in 2011 to 24% (95% CI, 21%-27%) in 2017 (P < .001). Among infants with culture-confirmed LOS, LP performance decreased from 58% (95% CI, 51%-65%) to 45% (95% CI, 38%-51%; P = .008). LP performance varied by center among all LOS evaluations (10%-59%, P < .001) and among those with culture-confirmed LOS (23%-79%, P < .001). LOM occurred in the absence of concurrent LOS in 27 of 167 cases (16%). The most common LOM isolates were coagulase-negative Staphylococcus (98 [59%]), Candida albicans (38 [23%]), and Escherichia coli (27 [16%]). Death or NDI occurred in 22 of 46 children (48%) with LOM due to coagulase-negative Staphylococcus, 43 of 67 (64%) due to all other bacterial pathogens, and 26 of 33 (79%) due to fungal pathogens. The adjusted relative risk of death or NDI was increased among children with LOM (aOR, 1.53; 95% CI, 1.04-2.25) and among those with LOS without LOM (aOR, 1.41; 95% CI, 1.29-1.54) compared with children with neither infection.

Conclusions and Relevance

In this cohort study, LP was performed with decreasing frequency, and the observed incidence of LOM also decreased. Both LOM and LOS were associated with increased risk of death or NDI; risk varied by LOM pathogen. The full association of LOM with outcomes of children born extremely preterm may be underestimated by current diagnostic practices.

Neonatal infections: Insights from a multicenter longitudinal research collaborative

For more than 30 years, the Neonatal Research Network (NRN) has conducted studies addressing the epidemiology of neonatal infections, including incidence, microbiology, maternal and neonatal risk factors, associated clinical findings, and outcomes. These studies have provided clinicians and policymakers critical data needed to inform national guidance for infection risk assessment and support daily practice. Further, NRN studies have prompted research into optimal approaches to infection diagnosis, treatment, and antimicrobial stewardship. In this article, we summarize the key findings of NRN infection-related studies, with an emphasis on those published in 2000 or later.

Contributions of the NICHD neonatal research network's generic database to documenting and advancing the outcomes of extremely preterm infants

The Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN) maintains a database of extremely preterm infants known as the Generic Database (GDB). Begun in 1987, this database now includes more than 91,000 infants, most of whom are extremely preterm (<29 weeks gestation). The GDB has been the backbone of the NRN, providing high quality, prospectively collected data to study the changing epidemiology of extreme prematurity and its outcomes over time. In addition, GDB data have been used to generate hypotheses for prospective studies and to develop new clinical trials by providing information about the numbers and characteristics of available subjects and the expected event rates for conditions and complications to be studied. Since its inception, the GDB has been the basis of more than 200 publications in peer-reviewed journals, many of which have had a significant impact on the field of neonatology.

Group B Streptococcus Infection in Extremely Preterm Neonates and Neurodevelopmental Outcomes at 2 Years

BACKGROUND

This study was performed to determine the incidence of group B Streptococcus (GBS) disease among extremely preterm infants and assess to risk of death or neurodevelopmental impairment (NDI) at a corrected age of 18-26 months.

METHODS

In this observational cohort study of infants enrolled in a multicenter registry, the incidence of GBS disease was assessed in infants born in 1998-2016 at 22-28 weeks' gestation and surviving for >12 hours. The composite outcome, death or NDI, was assessed in infants born in 1998-2014 at 22-26 weeks' gestation. Infection was defined as GBS isolation in blood or cerebrospinal fluid culture at ≤72 hours (early-onset disease [EOD]) or >72 hours (late-onset disease [LOD]) after birth. Using Poisson regression models, the outcome was compared in infants with GBS disease, infants infected with other pathogens, and uninfected infants.

RESULTS

The incidence of GBS EOD (2.70/1000 births [95% confidence interval (CI), 2.15-3.36]) and LOD (8.47/1000 infants [7.45-9.59]) did not change significantly over time. The adjusted relative risk of death/NDI was higher among infants with GBS EOD than in those with other infections (adjusted relative risk, 1.22 [95% CI, 1.02-1.45]) and uninfected infants (1.44 [1.23-1.69]). Risk of death/NDI did not differ between infants with GBS LOD and comparator groups. GBS LOD occurred at a significantly later age than non-GBS late-onset infection. Among infants surviving >30 days, the risk of death was higher with GBS LOD (adjusted relative risk, 1.90 [95% CI, 1.36-2.67]), compared with uninfected infants.

CONCLUSIONS

In a cohort of extremely preterm infants, the incidence of GBS disease did not change during the study period. The increased risk of death or NDI with GBS EOD, and of death among some infants with GBS LOD, supports the need for novel preventive strategies for disease reduction.

CLINICAL TRIALS REGISTRATION

NCT00063063.

Antimicrobial Susceptibility Profiles Among Neonatal Early-onset Sepsis Pathogens

BACKGROUND

Empiric administration of ampicillin and gentamicin is recommended for newborns at risk of early-onset sepsis (EOS). There are limited data on antimicrobial susceptibility of all EOS pathogens.

METHODS

Retrospective review of antimicrobial susceptibility data from a prospective EOS surveillance study of infants born ≥22 weeks' gestation and cared for in Neonatal Research Network centers April 2015-March 2017. Nonsusceptible was defined as intermediate or resistant on final result.

RESULTS

We identified 239 pathogens (235 bacteria, 4 fungi) in 235 EOS cases among 217,480 live-born infants. Antimicrobial susceptibility data were available for 189/239 (79.1%) isolates. Among 81 Gram-positive isolates with ampicillin and gentamicin susceptibility data, all were susceptible in vitro to either ampicillin or gentamicin. Among Gram-negative isolates with ampicillin and gentamicin susceptibility data, 72/94 (76.6%) isolates were nonsusceptible to ampicillin, 8/94 (8.5%) were nonsusceptible to gentamicin, and 7/96 (7.3%) isolates were nonsusceptible to both. Five percent or less of tested Gram-negative isolates were nonsusceptible to each of third or fourth generation cephalosporins, piperacillin-tazobactam, and carbapenems. Overall, we estimated that 8% of EOS cases were caused by isolates nonsusceptible to both ampicillin and gentamicin; these were most likely to occur among preterm, very-low birth weight infants.

CONCLUSIONS

The vast majority of contemporary EOS pathogens are susceptible to the combination of ampicillin and gentamicin. Clinicians may consider the addition of broader-spectrum therapy among newborns at highest risk of EOS, but we caution that neither the substitution nor the addition of 1 single antimicrobial agent is likely to provide adequate empiric therapy in all cases.

Mortality, In-Hospital Morbidity, Care Practices, and 2-Year Outcomes for Extremely Preterm Infants in the US, 2013-2018

IMPORTANCE

Despite improvement during recent decades, extremely preterm infants continue to contribute disproportionately to neonatal mortality and childhood morbidity.

OBJECTIVE

To review survival, in-hospital morbidities, care practices, and neurodevelopmental and functional outcomes at 22-26 months' corrected age for extremely preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

Prospective registry for extremely preterm infants born at 19 US academic centers that are part of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. The study included 10 877 infants born at 22-28 weeks' gestational age between January 1, 2013, and December 31, 2018, including 2566 infants born before 27 weeks between January 1, 2013, and December 31, 2016, who completed follow-up assessments at 22-26 months' corrected age. The last assessment was completed on August 13, 2019. Outcomes were compared with a similar cohort of infants born in 2008-2012 adjusting for gestational age.

EXPOSURES

Extremely preterm birth.

MAIN OUTCOMES AND MEASURES

Survival and 12 in-hospital morbidities were assessed, including necrotizing enterocolitis, infection, intracranial hemorrhage, retinopathy of prematurity, and bronchopulmonary dysplasia. Infants were assessed at 22-26 months' corrected age for 12 health and functional outcomes, including neurodevelopment, cerebral palsy, vision, hearing, rehospitalizations, and need for assistive devices.

RESULTS

The 10 877 infants were 49.0% female and 51.0% male; 78.3% (8495/10848) survived to discharge, an increase from 76.0% in 2008-2012 (adjusted difference, 2.0%; 95% CI, 1.0%-2.9%). Survival to discharge was 10.9% (60/549) for live-born infants at 22 weeks and 94.0% (2267/2412) at 28 weeks. Survival among actively treated infants was 30.0% (60/200) at 22 weeks and 55.8% (535/958) at 23 weeks. All in-hospital morbidities were more likely among infants born at earlier gestational ages. Overall, 8.9% (890/9956) of infants had necrotizing enterocolitis, 2.4% (238/9957) had early-onset infection, 19.9% (1911/9610) had late-onset infection, 14.3% (1386/9705) had severe intracranial hemorrhage, 12.8% (1099/8585) had severe retinopathy of prematurity, and 8.0% (666/8305) had severe bronchopulmonary dysplasia. Among 2930 surviving infants with gestational ages of 22-26 weeks eligible for follow-up, 2566 (87.6%) were examined. By 2-year follow-up, 8.4% (214/2555) of children had moderate to severe cerebral palsy, 1.5% (38/2555) had bilateral blindness, 2.5% (64/2527) required hearing aids or cochlear implants, 49.9% (1277/2561) had been rehospitalized, and 15.4% (393/2560) required mobility aids or other supportive devices. Among 2458 fully evaluated infants, 48.7% (1198/2458) had no or mild neurodevelopmental impairment at follow-up, 29.3% (709/2419) had moderate neurodevelopmental impairment, and 21.2% (512/2419) had severe neurodevelopmental impairment.

CONCLUSIONS AND RELEVANCE

Among extremely preterm infants born in 2013-2018 and treated at 19 US academic medical centers, 78.3% survived to discharge, a significantly higher rate than for infants born in 2008-2012. Among infants born at less than 27 weeks' gestational age, rehospitalization and neurodevelopmental impairment were common at 2 years of age.

Preeclampsia at delivery is associated with lower serum vitamin D and higher antiangiogenic factors: a case control study

BACKGROUND

Preeclampsia is characterized by decreased trophoblastic angiogenesis leading to abnormal invasion of spiral arteries, shallow implantation and resulting in compromised placentation with poor uteroplacental perfusion. Vitamin D plays an important role in pregnancy influencing implantation, angiogenesis and placental development. The objective of this study was to determine whether there is an association between serum vitamin D levels, and anti-angiogenic factors at the time of delivery and the occurrence of preeclampsia.

METHODS

This nested case control study analyzed frozen serum samples at the time of delivery and related clinical data from women with singleton liveborn pregnancies who had participated in studies of the NICHD Stillbirth Collaborative Research Network. Women with a recorded finding of preeclampsia and who had received magnesium sulfate treatment prior to delivery were considered index cases (N = 56). Women without a finding of preeclampsia were controls (N = 341).

RESULTS

Women with preeclampsia had 14.5% lower serum vitamin D levels than women in the control group (16.5 ng/ml vs. 19 ng/ml, p = 0.014) with 64.5% higher sFlt-1 levels (11,600 pg/ml vs. 7050 pg/ml, p < 0.001) and greater than 2 times higher endoglin levels (18.6 ng/ml vs. 8.7 ng/ml, < 0.001). After controlling for gestational age at delivery and maternal BMI, vitamin D levels were 0.88 times lower (P = 0.051), while endoglin levels were 2.5 times higher and sFlt-1 levels were 2.1 times higher than in control pregnancies (P < 0.001).

CONCLUSIONS

Women with preeclampsia at time of delivery have higher maternal antiangiogenetic factors and may have lower maternal serum vitamin D levels. These findings may lead to a better understanding of the underlying etiology of preeclampsia as well as possible modifiable treatment options which could include assuring adequate levels of maternal serum vitamin D prior to pregnancy.

Surgery-Associated Infections among Infants Born Extremely Preterm

OBJECTIVE

To assess the burden of invasive infection following surgery (surgery-associated infections [SAI]) among infants born extremely premature.

STUDY DESIGN

This was an observational, prospective study of infants born at gestational age 22-28 weeks hospitalized for >3 days, between April 1, 2011, to March 31, 2015, in academic centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. SAI was defined by culture-confirmed bacteremia, fungemia, or meningitis ≤14 days following a surgical procedure.

RESULTS

Of 6573 infants, 1154 (18%) who underwent surgery were of lower gestational age (mean [SD]: 25.5 [1.6] vs 26.2 [1.6], P < .001), lower birth weight (803 [220] vs 886 [244], P < .001), and more likely to have a major birth defect (10% vs 3%, P < .001); 64% had 1 surgery (range 1-10 per infant). Most underwent gastrointestinal procedures (873, 76%) followed by central nervous system procedures (150, 13%). Eighty-five (7%) infants had 90 SAIs (78 bacteremia, 5 fungemia, 1 bacteremia and meningitis, 6 meningitis alone). Coagulase-negative staphylococci were isolated in 36 (40%) SAI and were isolated with another organism in 5 episodes. Risk of SAI or death ≤14 days after surgery was greater after gastrointestinal compared with central nervous system procedures (16% vs 7%, adjusted relative risk [95% CI]: 1.95 [1.15-3.29], P = .01). Death ≤14 days after surgery occurred in 141 of the 1154 infants; 128 deaths occurred after gastrointestinal surgeries.

CONCLUSIONS

Surgical procedures were associated with bacteremia, fungemia, or meningitis in 7% of infants. The epidemiology of invasive postoperative infections as described in this report may inform the selection of empiric antimicrobial therapy and postoperative preventive care.

Initial Laparotomy Versus Peritoneal Drainage in Extremely Low Birthweight Infants With Surgical Necrotizing Enterocolitis or Isolated Intestinal Perforation: A Multicenter Randomized Clinical Trial

OBJECTIVE

The aim of this study was to determine which initial surgical treatment results in the lowest rate of death or neurodevelopmental impairment (NDI) in premature infants with necrotizing enterocolitis (NEC) or isolated intestinal perforation (IP).

SUMMARY BACKGROUND DATA

The impact of initial laparotomy versus peritoneal drainage for NEC or IP on the rate of death or NDI in extremely low birth weight infants is unknown.

METHODS

We conducted the largest feasible randomized trial in 20 US centers, comparing initial laparotomy versus peritoneal drainage. The primary outcome was a composite of death or NDI at 18 to 22 months corrected age, analyzed using prespecified frequentist and Bayesian approaches.

RESULTS

Of 992 eligible infants, 310 were randomized and 96% had primary outcome assessed. Death or NDI occurred in 69% of infants in the laparotomy group versus 70% with drainage [adjusted relative risk (aRR) 1.0; 95% confidence interval (CI): 0.87-1.14]. A preplanned analysis identified an interaction between preoperative diagnosis and treatment group (P = 0.03). With a preoperative diagnosis of NEC, death or NDI occurred in 69% after laparotomy versus 85% with drainage (aRR 0.81; 95% CI: 0.64-1.04). The Bayesian posterior probability that laparotomy was beneficial (risk difference <0) for a preoperative diagnosis of NEC was 97%. For preoperative diagnosis of IP, death or NDI occurred in 69% after laparotomy versus 63% with drainage (aRR, 1.11; 95% CI: 0.95-1.31); Bayesian probability of benefit with laparotomy = 18%.

CONCLUSIONS

There was no overall difference in death or NDI rates at 18 to 22 months corrected age between initial laparotomy versus drainage. However, the preoperative diagnosis of NEC or IP modified the impact of initial treatment.

Maternal serum fructosamine levels and stillbirth: a case-control study of the Stillbirth Collaborative Research Network

OBJECTIVE

To evaluate the association between maternal fructosamine levels at the time of delivery and stillbirth.

DESIGN

Secondary analysis of a case-control study.

SETTING

Multicentre study of five geographic catchment areas in the USA.

POPULATION

All singleton stillbirths with known diabetes status and fructosamine measurement, and representative live birth controls.

MAIN OUTCOME MEASURES

Fructosamine levels in stillbirths and live births among groups were adjusted for potential confounding factors, including diabetes. Optimal thresholds of fructosamine to discriminate stillbirth and live birth.

RESULTS

A total of 529 women with a stillbirth and 1499 women with a live birth were included in the analysis. Mean fructosamine levels were significantly higher in women with a stillbirth than in women with a live birth after adjustment (177 ± 3.05 versus 165 ± 2.89 μmol/L, P < 0.001). The difference in fructosamine levels between stillbirths and live births was greater among women with diabetes (194 ± 8.54 versus 162 ± 3.21 μmol/L), compared with women without diabetes (171 ± 2.50 versus 162 ± 2.56 μmol/L). The area under the curve (AUC) for fructosamine level and stillbirth was 0.634 (0.605-0.663) overall, 0.713 (0.624-0.802) with diabetes and 0.625 (0.595-0.656) with no diabetes.

CONCLUSIONS

Maternal fructosamine levels at the time of delivery were higher in women with stillbirth compared with women with live birth. Differences were substantial in women with diabetes, suggesting a potential benefit of glycaemic control in women with diabetes during pregnancy. The small differences noted in women without diabetes are not likely to justify routine screening in all cases of stillbirth.

TWEETABLE ABSTRACT

Maternal serum fructosamine levels are higher in women with stillbirth than in women with live birth, especially in women with diabetes.

Neurodevelopmental outcomes following neonatal late-onset sepsis and blood culture-negative conditions

OBJECTIVE

Determine risk of death or neurodevelopmental impairment (NDI) in infants with late-onset sepsis (LOS) versus late-onset, antibiotic-treated, blood culture-negative conditions (LOCNC).

DESIGN

Retrospective cohort study.

SETTING

24 neonatal centres.

PATIENTS

Infants born 1/1/2006-31/12/2014, at 22-26 weeks gestation, with birth weight 401-1000 g and surviving >7 days were included. Infants with early-onset sepsis, necrotising enterocolitis, intestinal perforation or both LOS and LOCNC were excluded.

EXPOSURES

LOS and LOCNC were defined as antibiotic administration for ≥5 days with and without a positive blood/cerebrospinal fluid culture, respectively. Infants with these diagnoses were also compared with infants with neither condition.

OUTCOMES

Death or NDI was assessed at 18-26 months corrected age follow-up. Modified Poisson regression models were used to estimate relative risks adjusting for covariates occurring ≤7 days of age.

RESULTS

Of 7354 eligible infants, 3940 met inclusion criteria: 786 (20%) with LOS, 1601 (41%) with LOCNC and 1553 (39%) with neither. Infants with LOS had higher adjusted relative risk (95% CI) for death/NDI (1.14 (1.05 to 1.25)) and death before follow-up (1.71 (1.44 to 2.03)) than those with LOCNC. Among survivors, risk for NDI did not differ between the two groups (0.99 (0.86 to 1.13)) but was higher for LOCNC infants (1.17 (1.04 to 1.31)) compared with unaffected infants.

CONCLUSIONS

Infants with LOS had higher risk of death, but not NDI, compared with infants with LOCNC. Surviving infants with LOCNC had higher risk of NDI compared with unaffected infants. Improving outcomes for infants with LOCNC requires study of the underlying conditions and the potential impact of antibiotic exposure.

Withholding or withdrawing life-sustaining treatment in extremely low gestational age neonates

OBJECTIVE

To identify sociodemographic and clinical factors associated with withholding or withdrawing life-sustaining treatment (WWLST) for extremely low gestational age neonates.

DESIGN

Observational study of prospectively collected registry data from 19 National Institute of Child Health and Human Development Neonatal Research Network centres on neonates born at 22-28 weeks gestation who died >12 hours through 120 days of age during 2011-2016. Sociodemographic and clinical factors were compared between infants who died following WWLST and without WWLST.

RESULTS

Of 1168 deaths, 67.1% occurred following WWLST. Withdrawal of assisted ventilation (97.4%) was the primary modality. WWLST rates were inversely proportional to gestational age. Life-sustaining treatment was withheld or withdrawn more often for non-Hispanic white infants than for non-Hispanic black infants (72.7% vs 60.4%; 95% CI 1.00 to 1.92) or Hispanic infants (72.7% vs 67.2%; 95% CI 1.32 to 3.72). WWLST rates varied across centres (38.6-92.6%; p<0.001). The centre with the highest rate had adjusted odds 4.89 times greater than the average (95% CI 1.18 to 20.18). The adjusted odds of WWLST were higher for infants with necrotiing enterocolitis (OR 1.77, 95% CI 1.21 to 2.59) and severe brain injury (OR 1.98, 95% CI 1.44 to 2.74).

CONCLUSIONS

Among infants who died, WWLST rates varied widely across centres and were associated with gestational age, race, ethnicity, necrotiing enterocolitis, and severe brain injury. Further exploration is needed into how race, centre, and approaches to care of infants with necrotiing enterocolitis and severe brain injury influence WWLST.

Stillbirth and fetal anomalies: secondary analysis of a case-control study

OBJECTIVE

Approximately 10% of stillbirths are attributed to fetal anomalies, but anomalies are also common in live births. We aimed to assess the relationship between anomalies, by system and stillbirth.

DESIGN

Secondary analysis of a prospective, case-control study.

SETTING

Multicentre, 59 hospitals in five regional catchment areas in the USA.

POPULATION OR SAMPLE

All stillbirths and representative live birth controls.

METHODS

Standardised postmortem examinations performed in stillbirths, medical record abstraction for stillbirths and live births.

MAIN OUTCOME MEASURES

Incidence of major anomalies, by type, compared between stillbirths and live births with univariable and multivariable analyses using weighted analysis to account for study design and differential consent.

RESULTS

Of 465 singleton stillbirths included, 23.4% had one or more major anomalies compared with 4.3% of 1871 live births. Having an anomaly increased the odds of stillbirth; an increasing number of anomalies was more highly associated with stillbirth. Regardless of organ system affected, the presence of an anomaly increased the odds of stillbirth. These relationships remained significant if stillbirths with known genetic abnormalities were excluded. After multivariable analyses, the adjusted odds ratio (aOR) of stillbirth for any anomaly was 4.33 (95% CI 2.80-6.70) and the systems most strongly associated with stillbirth were cystic hygroma (aOR 29.97, 95% CI 5.85-153.57), and thoracic (aOR16.18, 95% CI 4.30-60.94) and craniofacial (aOR 35.25, 95% CI 9.22-134.68) systems.

CONCLUSIONS

In pregnancies affected by anomalies, the odds of stillbirth are higher with increasing numbers of anomalies. Anomalies of nearly any organ system increased the odds of stillbirth even when adjusting for gestational age and maternal race.

TWEETABLE ABSTRACT

Stillbirth risk increases with anomalies of nearly any organ system and with number of anomalies seen.

Early-Onset Neonatal Sepsis 2015 to 2017, the Rise of Escherichia coli, and the Need for Novel Prevention Strategies

IMPORTANCE

Early-onset sepsis (EOS) remains a potentially fatal newborn condition. Ongoing surveillance is critical to optimize prevention and treatment strategies.

OBJECTIVE

To describe the current incidence, microbiology, morbidity, and mortality of EOS among a cohort of term and preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

This prospective surveillance study included a cohort of infants born at a gestational age (GA) of at least 22 weeks and birth weight of greater than 400 g from 18 centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network from April 1, 2015, to March 31, 2017. Data were analyzed from June 14, 2019, to January 28, 2020.

MAIN OUTCOMES AND MEASURES

Early-onset sepsis defined by isolation of pathogenic species from blood or cerebrospinal fluid culture within 72 hours of birth and antibiotic treatment for at least 5 days or until death.

RESULTS

A total of 235 EOS cases (127 male [54.0%]) were identified among 217 480 newborns (1.08 [95% CI, 0.95-1.23] cases per 1000 live births). Incidence varied significantly by GA and was highest among infants with a GA of 22 to 28 weeks (18.47 [95% CI, 14.57-23.38] cases per 1000). No significant differences in EOS incidence were observed by sex, race, or ethnicity. The most frequent pathogens were Escherichia coli (86 [36.6%]) and group B streptococcus (GBS; 71 [30.2%]). E coli disease primarily occurred among preterm infants (68 of 131 [51.9%]); GBS disease primarily occurred among term infants (54 of 104 [51.9%]), with 24 of 45 GBS cases (53.3%) seen in infants born to mothers with negative GBS screening test results. Intrapartum antibiotics were administered to 162 mothers (68.9%; 110 of 131 [84.0%] preterm and 52 of 104 [50.0%] term), most commonly for suspected chorioamnionitis. Neonatal empirical antibiotic treatment most frequently included ampicillin and gentamicin. All GBS isolates were tested, but only 18 of 81 (22.2%) E coli isolates tested were susceptible to ampicillin; 6 of 77 E coli isolates (7.8%) were resistant to both ampicillin and gentamicin. Nearly all newborns with EOS (220 of 235 [93.6%]) displayed signs of illness within 72 hours of birth. Death occurred in 38 of 131 infected infants with GA of less than 37 weeks (29.0%); no term infants died. Compared with earlier surveillance (2006-2009), the rate of E coli infection increased among very low-birth-weight (401-1500 g) infants (8.68 [95% CI, 6.50-11.60] vs 5.07 [95% CI, 3.93-6.53] per 1000 live births; P = .008).

CONCLUSIONS AND RELEVANCE

In this study, EOS incidence and associated mortality disproportionately occurred in preterm infants. Contemporary cases have demonstrated the limitations of current GBS prevention strategies. The increase in E coli infections among very low-birth-weight infants warrants continued study. Ampicillin and gentamicin remained effective antibiotics in most cases, but ongoing surveillance should monitor antibiotic susceptibilities of EOS pathogens.

Racial/Ethnic Disparities Among Extremely Preterm Infants in the United States From 2002 to 2016

IMPORTANCE

Racial/ethnic disparities in quality of care among extremely preterm infants are associated with adverse outcomes.

OBJECTIVE

To assess whether racial/ethnic disparities in major outcomes and key care practices were changing over time among extremely preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

This observational cohort study used prospectively collected data from 25 US academic medical centers. Participants included 20 092 infants of 22 to 27 weeks' gestation with a birth weight of 401 to 1500 g born at centers participating in the National Institute of Child Health and Human Development Neonatal Research Network from 2002 to 2016. Of these infants, 9316 born from 2006 to 2014 were eligible for follow-up at 18 to 26 months' postmenstrual age (excluding 5871 infants born before 2006, 2594 infants born after 2014, and 2311 ineligible infants including 64 with birth weight >1000 g and 2247 infants with gestational age >26 6/7 weeks), of whom 745 (8.0%) did not have known follow-up outcomes at 18 to 26 months.

MAIN OUTCOMES AND MEASURES

Rates of mortality, major morbidities, and care practice use over time were evaluated using models adjusted for baseline characteristics, center, and birth year. Data analyses were conducted from 2018 to 2019.

RESULTS

In total, 20 092 infants with a mean (SD) gestational age of 25.1 (1.5) weeks met the inclusion criteria and were available for the primary outcome: 8331 (41.5%) black infants, 3701 (18.4%) Hispanic infants, and 8060 (40.1%) white infants. Hospital mortality decreased over time in all groups. The rate of improvement in hospital mortality over time did not differ among black and Hispanic infants compared with white infants (black infants went from 35% to 24%, Hispanic infants went from 32% to 27%, and white infants went from 30% to 22%; P = .59 for race × year interaction). The rates of late-onset sepsis among black infants (went from 37% to 24%) and Hispanic infants (went from 45% to 23%) were initially higher than for white infants (went from 36% to 25%) but decreased more rapidly and converged during the most recent years (P = .02 for race × year interaction). Changes in rates of other major morbidities did not differ by race/ethnicity. Death before follow-up decreased over time (from 2006 to 2014: black infants, 14%; Hispanic infants, 39%, white infants, 15%), but moderate-severe neurodevelopmental impairment increased over time in all racial/ethnic groups (increase from 2006 to 2014: black infants, 70%; Hispanic infants, 123%; white infants, 130%). Rates of antenatal corticosteroid exposure (black infants went from 72% to 90%, Hispanic infants went from 73% to 83%, and white infants went from 86% to 90%; P = .01 for race × year interaction) and of cesarean delivery (black infants went from 45% to 59%, Hispanic infants went from 49% to 59%, and white infants went from 62% to 63%; P = .03 for race × year interaction) were initially lower among black and Hispanic infants compared with white infants, but these differences decreased over time.

CONCLUSIONS AND RELEVANCE

Among extremely preterm infants, improvements in adjusted rates of mortality and most major morbidities did not differ by race/ethnicity, but rates of neurodevelopmental impairment increased in all groups. There were narrowing racial/ethnic disparities in important care practices, including the use of antenatal corticosteroids and cesarean delivery.

Impact of Early-Onset Sepsis and Antibiotic Use on Death or Survival with Neurodevelopmental Impairment at 2 Years of Age among Extremely Preterm Infants

OBJECTIVE

To evaluate the hypothesis that early-onset sepsis increases risk of death or neurodevelopmental impairment (NDI) among preterm infants; and that among infants without early-onset sepsis, prolonged early antibiotics alters risk of death/NDI.

STUDY DESIGN

Retrospective cohort study of infants born at the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network centers (2006-2014) at 22-26 weeks of gestation and birth weight 401-1000 g. Early-onset sepsis defined as growth of a pathogen from blood or cerebrospinal fluid culture ≤72 hours after birth. Prolonged early antibiotics was defined as antibiotics initiated ≤72 hours and continued ≥5 days without culture-confirmed infection, necrotizing enterocolitis, or spontaneous perforation. Primary outcome was death before follow-up or NDI assessed at 18-26 months corrected age. Poisson regression was used to estimate adjusted relative risk (aRR) and CI for early-onset sepsis outcomes. A propensity score for receiving prolonged antibiotics was derived from early clinical factors and used to match infants (1:1) with and without prolonged antibiotic exposure. Log binomial models were used to estimate aRR for outcomes in matched infants.

RESULTS

Among 6565 infants, those with early-onset sepsis had higher aRR (95% CI) for death/NDI compared with infants managed with prolonged antibiotics (1.18 [1.06-1.32]) and to infants without prolonged antibiotics (1.23 [1.10-1.37]). Propensity score matching was achieved for 4362 infants. No significant difference in death/NDI (1.04 [0.98-1.11]) was observed with or without prolonged antibiotics among the matched cohort.

CONCLUSIONS

Early-onset sepsis was associated with increased risk of death/NDI among extremely preterm infants. Among matched infants without culture-confirmed infection, prolonged early antibiotic administration was not associated with death/NDI.

Behavior Profiles at 2 Years for Children Born Extremely Preterm with Bronchopulmonary Dysplasia

OBJECTIVE

To characterize behavior of 2-year-old children based on the severity of bronchopulmonary dysplasia (BPD).

STUDY DESIGN

We studied children born at 22-26 weeks of gestation and assessed at 22-26 months of corrected age with the Child Behavior Checklist (CBCL). BPD was classified by the level of respiratory support at 36 weeks of postmenstrual age. CBCL syndrome scales were the primary outcomes. The relationship between BPD grade and behavior was evaluated, adjusting for perinatal confounders. Mediation analysis was performed to evaluate whether cognitive, language, or motor skills mediated the effect of BPD grade on behavior.

RESULTS

Of 2310 children, 1208 (52%) had no BPD, 806 (35%) had grade 1 BPD, 177 (8%) had grade 2 BPD, and 119 (5%) had grade 3 BPD. Withdrawn behavior (P < .001) and pervasive developmental problems (P < .001) increased with worsening BPD grade. Sleep problems (P = .008) and aggressive behavior (P = .023) decreased with worsening BPD grade. Children with grade 3 BPD scored 2 points worse for withdrawn behavior and pervasive developmental problems and 2 points better for externalizing problems, sleep problems, and aggressive behavior than children without BPD. Cognitive, language, and motor skills mediated the effect of BPD grade on the attention problems, emotionally reactive, somatic complaints, and withdrawn CBCL syndrome scales (P values < .05).

CONCLUSIONS

BPD grade was associated with increased risk of withdrawn behavior and pervasive developmental problems but with decreased risk of sleep problems and aggressive behavior. The relationship between BPD and behavior is complex. Cognitive, language, and motor skills mediate the effects of BPD grade on some problem behaviors.

The association between gestational weight gain z-score and stillbirth: a case-control study

BACKGROUND

There is limited information on potentially modifiable risk factors for stillbirth, such as gestational weight gain (GWG). Our purpose was to explore the association between GWG and stillbirth using the GWG z-score.

METHODS

We analyzed 479 stillbirths and 1601 live births from the Stillbirth Collaborative Research Network case-control study. Women with triplets or monochorionic twins were excluded from analysis. We evaluated the association between GWG z-score (modeled as a restricted cubic spline with knots at the 5th, 50th, and 95th percentiles) and stillbirth using multivariable logistic regression with generalized estimating equations, adjusting for pre - pregnancy body mass index (BMI) and other confounders. In addition, we conducted analyses stratified by pre - pregnancy BMI category (normal weight, overweight, obese).

RESULTS

Mean GWG was 18.95 (SD 17.6) lb. among mothers of stillbirths and 30.89 (SD 13.3) lb. among mothers of live births; mean GWG z-score was - 0.39 (SD 1.5) among mothers of cases and - 0.17 (SD 0.9) among control mothers. In adjusted analyses, the odds of stillbirth were elevated for women with very low GWG z-scores (e.g., adjusted odds ratio (aOR) and 95% Confidence Interval (CI) for z-score - 1.5 SD versus 0 SD: 1.52 (1.30, 1.78); aOR (95% CI) for z-score - 2.5 SD versus 0 SD: 2.36 (1.74, 3.20)). Results differed slightly by pre - pregnancy BMI. The odds of stillbirth were slightly elevated among women with overweight BMI and GWG z-scores ≥1 SD (e.g., aOR (95% CI) for z-score of 1.5 SD versus 0 SD: 1.84 (0.97, 3.50)).

CONCLUSIONS

GWG z-scores below - 1.5 SD are associated with increased odds of stillbirth.

Prolonged duration of early antibiotic therapy in extremely premature infants

BACKGROUND

Prolonged early antibiotics in extremely premature infants may have negative effects. We aimed to assess prevalence and outcomes of provision of prolonged early antibiotics to extremely premature infants in the absence of culture-confirmed infection or NEC.

METHODS

Cohort study of infants from 13 centers born without a major birth defect from 2008-2014 who were 401-1000 grams birth weight, 22-28 weeks gestation, and survived ≥5 days without culture-confirmed infection, NEC, or spontaneous intestinal perforation. We determined the proportion of infants who received prolonged early antibiotics, defined as ≥5 days of antibiotic therapy started at ≤72 h of age, by center and over time. Associations between prolonged early antibiotics and adverse outcomes were assessed using multivariable logistic regression.

RESULTS

A total of 5730 infants were included. The proportion of infants receiving prolonged early antibiotics varied from 30-69% among centers and declined from 49% in 2008 to 35% in 2014. Prolonged early antibiotics was not significantly associated with death (adjusted odds ratio 1.17 [95% CI: 0.99-1.40], p = 0.07) and was not associated with NEC.

CONCLUSIONS

The proportion of extremely premature infants receiving prolonged early antibiotics decreased, but significant center variation persists. Prolonged early antibiotics were not significantly associated with increased odds of death or NEC.

Interpregnancy interval and risk of stillbirth: a population-based case control study

PURPOSE

We examined the association between interpregnancy intervals (IPIs) and stillbirth (defined as fetal death ≥20 weeks), as both short and long IPIs have been associated with adverse perinatal outcomes. Prior pregnancy loss is also a known risk factor for stillbirth, and women who suffer a prior loss often have shorter IPIs. For these reasons, we also sought to quantify the proportion of the association between prior pregnancy loss and subsequent stillbirth risk that may be attributed to a short IPI.

METHODS

We used data from the Stillbirth Collaborative Research Network, a multisite case-control study conducted in 2006-2008, restricted to singleton pregnancies among multiparous or multigravid women (985 controls and 291 cases). We accounted for complex sample design and nonparticipation with weighted multivariable logistic regression.

RESULTS

In the adjusted models, IPIs <6 months, as compared with a reference of 18-23 months, were associated with increased odds of stillbirth (aOR 1.6, 95% CI: 0.8, 3.4). Long IPIs (60-100 months) were also associated with an increased odds of stillbirth (aOR 2.4, 95% CI: 1.2, 4.5). After control for covariates, about one-fifth (21.2%) of the association of prior pregnancy loss (stillbirth, ectopic pregnancy, molar pregnancy, or spontaneous abortion) and stillbirth may be attributable to a short IPI.

CONCLUSIONS

Our results suggest that women who experience a prior pregnancy loss may benefit from additional counseling on adequate birth spacing to reduce subsequent stillbirth risk.

Discordance in Antenatal Corticosteroid Use and Resuscitation Following Extremely Preterm Birth

OBJECTIVE

To describe discordance in antenatal corticosteroid use and resuscitation following extremely preterm birth and its relationship with infant survival and neurodevelopment.

STUDY DESIGN

A multicenter cohort study of 4858 infants 22-26 weeks of gestation born 2006-2011 at 24 US hospitals participating in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network, with follow-up through 2013. Survival and neurodevelopmental outcomes were available at 18-22 months of corrected age for 4576 (94.2%) infants. We described antenatal interventions, resuscitation, and infant outcomes. We modeled the effect on infant outcomes of each hospital increasing antenatal corticosteroid exposure for resuscitated infants born at 22-24 weeks of gestation to rates observed at 25-26 weeks of gestation.

RESULTS

Discordant antenatal corticosteroid use and resuscitation, where one and not the other occurred, were more frequent for births at 22 and 23 but not 24 weeks (rate ratio [95% CI] at 22 weeks: 1.7 [1.3-2.2]; 23 weeks: 2.6 [2.2-3.2]; 24 weeks: 1.0 [0.8-1.2]) when compared with 25-26 weeks. Among infants resuscitated at 23 weeks, adjusting each hospital's rate of antenatal corticosteroid use to the average at 25-26 weeks (89.2%) was projected to increase infant survival by 7.1% (95% CI 5.4-8.8%) and survival without severe impairment by 6.4% (95% CI 4.7-8.1%). No significant change in outcomes was projected for infants resuscitated at 22 weeks, where few (n = 22) resuscitated infants received antenatal corticosteroids.

CONCLUSIONS

Infants born at 23 weeks were more frequently resuscitated without antenatal corticosteroids than other extremely preterm infants. When resuscitation is intended, consistent provision of antenatal corticosteroids may increase infant survival and survival without impairment.

TRIAL REGISTRATION

ClinicalTrials.govNCT00063063 (Generic Database) and NCT00009633 (Follow-Up Study).

Outcomes of Extremely Preterm Infants With Birth Weight Less Than 400 g

IMPORTANCE

Birth weight (BW) is an important predictor of mortality and morbidity. At extremely early gestational ages (GAs), BW may influence decisions regarding initiation of resuscitation.

OBJECTIVE

To characterize outcomes of liveborn infants with a BW less than 400 g.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective multicenter cohort study analyzed extremely preterm infants born between January 2008 and December 2016 within the National Institute of Child Health and Human Development Neonatal Research Network. Infants with a BW less than 400 g and a GA of 22 to 26 weeks were included. Active treatment was defined as the provision of any potentially lifesaving intervention after birth. Survival was analyzed for the entire cohort; neurodevelopmental impairment (NDI) was examined for those born between January 2008 and December 2015 (birth years with outcomes available for analysis). Neurodevelopmental impairment at 18 to 26 months' corrected age (CA) was defined as a Bayley Scales of Infant and Toddler Development, Third Edition, cognitive composite score less than 85, a motor composite score less than 85, moderate or severe cerebral palsy, gross motor function classification system score of 2 or greater, bilateral blindness, and/or hearing impairment. Data were analyzed from September 2017 to October 2018.

EXPOSURES

Birth weight less than 400 g.

MAIN OUTCOMES AND MEASURES

The primary outcome was survival to discharge among infants who received active treatment. Analysis of follow-up data was limited to infants born from 2008 to 2015 to ensure children had reached assessment age. Within this cohort, neurodevelopmental outcomes were assessed for infants who survived to 18 to 26 months' CA and returned for a comprehensive visit.

RESULTS

Of the 205 included infants, 121 (59.0%) were female, 133 (64.9%) were singletons, and 178 (86.8%) were small for gestational age. Almost half (101 of 205 [49.3%]) received active treatment at birth. A total of 26 of 205 infants (12.7%; 95% CI, 8.5-18.9) overall survived to discharge, and 26 of 101 actively treated infants (25.7%; 95% CI, 17.6-35.4) survived to discharge. Within the subset of infants with a BW less than 400 g and a GA of 22 to 23 weeks, 6 of 36 actively treated infants (17%; 95% CI, 6-33) survived to discharge. Among infants born between 2008 and 2015, 23 of 90 actively treated infants (26%; 95% CI, 17-36) survived to discharge. Two infants died after discharge, and 2 were lost to follow-up. Thus, 19 of 90 actively treated infants (21%; 95% CI, 13-31) were evaluated at 18 to 26 months' CA. Moderate or severe NDI occurred in 14 of 19 infants (74%).

CONCLUSIONS AND RELEVANCE

Infants born with a BW less than 400 g are at high risk of mortality and significant morbidity. Although 21% of infants survived to 18 to 26 months' CA with active treatment, NDI was common among survivors.

Genetic variants associated with patent ductus arteriosus in extremely preterm infants

OBJECTIVE

Patent ductus arteriosus (PDA) is a commonly observed condition in preterm infants. Prior studies have suggested a role for genetics in determining spontaneous ductal closure. Using samples from a large neonatal cohort we tested the hypothesis that common genetic variations are associated with PDA in extremely preterm infants.

STUDY DESIGN

Preterm infants (n = 1013) enrolled at NICHD Neonatal Research Network sites were phenotyped for PDA. DNA was genotyped for 1634 single nucleotide polymorphisms (SNPs) from candidate genes. Analyses were adjusted for ancestral eigenvalues and significant epidemiologic variables.

RESULTS

SNPs in several genes were associated with the clinical diagnosis of PDA and with surgical ligation in extremely preterm neonates diagnosed with PDA (p < 0.01). None of the associations were significant after correction for multiple comparisons.

CONCLUSION

We identified several common genetic variants associated with PDA. These findings may inform further studies on genetic risk factors for PDA in preterm infants.

Neurodevelopmental outcomes among extremely premature infants with linear growth restriction

OBJECTIVE

To compare neurodevelopmental outcomes in linear growth-restricted (LGR) infants born <29 weeks with and without weight gain out of proportion to linear growth.

STUDY DESIGN

We compared 2-year neurodevelopmental outcomes between infants with and without LGR and between LGR infants with and without weight gain out of proportion to linear growth. The outcomes were Bayley-III cognitive, motor, and language scores, cerebral palsy, Gross Motor Function Classification System (GMFCS) level ≥ 2, and neurodevelopmental impairment.

RESULT

In total, 1227 infants were analyzed. LGR infants were smaller and less mature at birth, had higher BMI, and had lower Bayley-III language scores (82.3 vs. 85.0, p < 0.05). Among infants with LGR, infants with high BMI had lower language scores compared with those with low-to-normal BMI (80.8 vs. 83.3, p < 0.05), and were more likely to have GMFCS level ≥2 and neurodevelopmental impairment.

CONCLUSION

Among infants with LGR, weight gain out of proportion to linear growth was associated with poorer neurodevelopmental outcomes.

Associations Between the Features of Gross Placental Morphology and Birthweight

The placenta plays a critical role in regulating fetal growth. Recent studies suggest that there may be sex-specific differences in placental development. The purpose of our study was to evaluate the associations between birthweight and placental morphology in models adjusted for covariates and to assess sex-specific differences in these associations. We analyzed data from the Stillbirth Collaborative Research Network's population-based case-control study conducted between 2006 and 2008, which recruited cases of stillbirth and population-based controls in 5 states. Our analysis was restricted to singleton live births with a placental examination (n = 1229). Characteristics of placental morphology evaluated include thickness, surface area, difference in diameters, shape, and umbilical cord insertion site. We used linear regression to model birthweight as a function of placental morphology and covariates. Surface area had the greatest association with birthweight; a reduction in surface area of 83 cm², which reflects the interquartile range, is associated with a 260.2-g reduction in birthweight (95% confidence interval, -299.9 to -220.6), after adjustment for other features of placental morphology and covariates. Reduced placental thickness was also associated with lower birthweight. These associations did not differ between males and females. Our results suggest that reduced placental thickness and surface area are independently associated with lower birthweight and that these relationships are not related to sex.

Weaning of Moderately Preterm Infants from the Incubator to the Crib: A Randomized Clinical Trial

OBJECTIVE

To assess whether length of hospital stay is decreased among moderately preterm infants weaned from incubator to crib at a lower vs higher weight.

STUDY DESIGN

This trial was conducted in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Infants with gestational ages 29-33 weeks, birthweight <1600 g, and in an incubator were randomly assigned to a weaning weight of 1600 or 1800 g. Within 60 to 100 g of weaning weight, the incubator temperature was decreased by 1.0°C to 1.5°C every 24 hours until 28.0°C. The infants were weaned to the crib following stable temperature at 36.5°C to 37.4°C for 8 to 12 hours. Clothing and bedcoverings were standardized. The primary outcome was length of hospital stay from birth to discharge; secondary outcomes included length of stay and growth velocity from weaning to discharge. Adverse events were monitored.

RESULTS

Of 1565 infants screened, 885 were eligible, and 366 enrolled-187 to the 1600-g and 179 to the 1800-g group. Maternal and neonatal characteristics did not differ among weight groups. Length of hospital stay was a median of 43 days in the lower and 41 days in the higher weight group (P = .12). Growth velocity from completion of weaning to discharge was higher in the lower weight group, 13.7 g/kg/day vs 12.8 g/kg/day (P = .005). Groups did not differ in adverse events.

CONCLUSIONS

Among moderately preterm neonates, weaning from incubator to crib at a lower weight did not decrease length of stay, but was safe and was accompanied by higher weight gain after weaning.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02160002.

Prolonged respiratory support of any type impacts outcomes of extremely low birth weight infants

OBJECTIVES

This study tested the hypothesis that longer duration of any type of respiratory support is associated with an increased rate of death or neurodevelopmental impairment (NDI) at 18-22 months.

METHODS

Retrospective cohort study using the Generic Database of NICHD Neonatal Research Network from 2006 to 2010. Infants were born at <27 weeks gestational age with birth weights of 401-1000 g. Respiratory support received during initial hospitalization from birth was characterized as follows: no support, only invasive support, only non-invasive support or mixed invasive, and non-invasive support. The primary outcome was death after 24 h of life or NDI at 18-22 months corrected age.

RESULTS

In a cohort of 3651 infants, 1494 (40.9%) died or had NDI. Cumulative respiratory support of any type beyond 60 days was associated with the likelihood of death or NDI. Infants who only received invasive support had the highest rate (89.1%), followed by those received mixed support (26.1%). Infants who received only non-invasive support had the lowest rate (7.7%). When compared to the only non-invasive support group, both invasive [OR 62.7 (95%CI 25.7, 152.6)] and mixed [OR 6.1 (95%CI 2.6, 14.4)] support groups were significantly more likely to die or have NDI.

CONCLUSION

Prolonged respiratory support, whether invasive or non-invasive, is associated with increased odds of a poor outcome. The proportion of infants with a poor outcome increased in a dose dependent manner by two factors: the cumulative duration of respiratory support beyond 60 days, and the extent to which invasive support is provided.

Neonatal Morbidities among Moderately Preterm Infants with and without Exposure to Antenatal Corticosteroids

OBJECTIVE

We aimed to compare the rates of "surfactant treated respiratory disease" and other neonatal morbidities among moderately preterm (MPT) infants exposed to no, partial, or a complete course of antenatal corticosteroids (ANS).

STUDY DESIGN

This observational cohort study evaluated MPT infants (29^0/7-33^6/7 weeks' gestational age), born between January 2012 and November 2013 and enrolled in the "MPT Registry" of the National Institute of Child Health and Human Development Neonatal Research Network.

RESULTS

Data were available for 5,886 infants, including 676 with no exposure, 1225 with partial, and 3,985 with a complete course of ANS. Among no, partial, and complete ANS groups, respectively, there were significant differences in rates of delivery room resuscitation (4.1, 1.4, and 1.2%), surfactant-treated respiratory disease (26.5, 26.3, and 20%), and severe intracranial hemorrhage (3, 2, and 0.8%). Complete ANS course was associated with lower surfactant-treated respiratory disease, compared with partial ANS (odds ratio [OR] 0.62; 95% confidence interval [CI] 0.52-0.74), and no ANS groups (OR 0.52; 95% CI 0.41-0.66) on adjusted analysis.

CONCLUSION

In MPT infants, ANS exposure is associated with lower delivery room resuscitation, surfactant-treated respiratory disease, and severe intracranial hemorrhage; with the lowest frequency of morbidities associated with a complete course.

Stillbirth, Inflammatory Markers, and Obesity: Results from the Stillbirth Collaborative Research Network

BACKGROUND

Obesity is associated with increased risk of stillbirth, although the mechanisms are unknown. Obesity is also associated with inflammation. Serum ferritin, C-reactive protein, white blood cell count, and histologic chorioamnionitis are all markers of inflammation.

OBJECTIVE

This article determines if inflammatory markers are associated with stillbirth and body mass index (BMI). Additionally, we determined whether inflammatory markers help to explain the known relationship between obesity and stillbirth.

STUDY DESIGN

White blood cell count was assessed at admission to labor and delivery, maternal serum for assessment of various biomarkers was collected after study enrollment, and histologic chorioamnionitis was based on placental histology. These markers were compared for stillbirths and live births overall and within categories of BMI using analysis of variance on logarithmic-transformed markers and logistic regression for dichotomous variables. The impact of inflammatory markers on the association of BMI categories with stillbirth status was assessed using crude and adjusted odds ratios (COR and AOR, respectively) from logistic regression models. The interaction of inflammatory markers and BMI categories on stillbirth status was also assessed through logistic regression. Additional logistic regression models were used to determine if the association of maternal serum ferritin with stillbirth is different for preterm versus term births. Analyses were weighted for the overall population from which this sample was derived.

RESULTS

A total of 497 women with singleton stillbirths and 1,414 women with live births were studied with prepregnancy BMI (kg/m²) categorized as normal (18.5-24.9), overweight (25.0-29.9), or obese (30.0 + ). Overweight (COR, 1.48; 95% confidence interval [CI]: 1.14-1.94) and obese women (COR, 1.60; 95% CI: 1.23-2.08) were more likely than normal weight women to experience stillbirth. Serum ferritin levels were higher (geometric mean: 37.4 ng/mL vs. 23.3, p < 0.0001) and C-reactive protein levels lower (geometric mean: 2.9 mg/dL vs. 3.3, p = 0.0279), among women with stillbirth compared with live birth. Elevated white blood cell count (15.0 uL × 10³ or greater) was associated with stillbirth (21.2% SB vs. 10.0% live birth, p < 0.0001). Histologic chorioamnionitis was more common (33.2% vs. 15.7%, p < 0.0001) among women with stillbirth compared with those with live birth. Serum ferritin, C-reactive protein, and chorioamnionitis had little impact on the ORs associating stillbirth with overweight or obesity. Adjustment for elevated white blood cell count did not meaningfully change the OR for stillbirth in overweight versus normal weight women. However, the stillbirth OR for obese versus normal BMI changed by more than 10% when adjusting for histologic chorioamnionitis (AOR, 1.38; 95% CI: 1.02-1.88), indicating confounding. BMI by inflammatory marker interaction terms were not significant. The association of serum ferritin levels with stillbirth was stronger among preterm births (p = 0.0066).

CONCLUSION

Maternal serum ferritin levels, elevated white blood cell count, and histologic chorioamnionitis were positively and C-reactive protein levels negatively associated with stillbirth. Elevated BMIs, both overweight and obese, were associated with stillbirth when compared with women with normal BMI. None of the inflammatory markers fully accounted for the relationship between obesity and stillbirth. The association of maternal serum ferritin with stillbirth was stronger in preterm than term stillbirths.

Antifungal Susceptibility and Clinical Outcome in Neonatal Candidiasis

BACKGROUND

Invasive candidiasis is an important cause of sepsis in extremely low birth weight infants (ELBW, < 1000 g), is often fatal, and frequently results in neurodevelopmental impairment (NDI) among survivors. We sought to assess the antifungal minimum inhibitory concentration (MIC) distribution for Candida in ELBW infants and evaluate the association between antifungal resistance and death or NDI.

METHODS

This was a secondary analysis of a National Institute of Child Health and Human Development Neonatal Research Network study. MIC values were determined for fluconazole, amphotericin B and micafungin. NDI was assessed at 18-22 months adjusted age using the Bayley Scales of Infant Development. An infant was defined as having a resistant Candida isolate if ≥ 1 positive cultures from normally sterile sites (blood, cerebrospinal fluid, or urine) were resistant to ≥ 1 antifungal agent. In addition to resistance status, we categorized fungal isolates according to MIC values (low and high). The association between death/NDI and MIC level was determined using logistic regression, controlling for gestational age and Bayley Scales of Infant Development (II or III).

RESULTS

Among 137 ELBW infants with IC, MICs were determined for 308 isolates from 110 (80%) infants. Three Candida isolates from 3 infants were resistant to fluconazole. None were resistant to amphotericin B or micafungin. No significant difference in death, NDI, or death/NDI between groups with low and high MICs was observed.

CONCLUSIONS

Antifungal resistance was rare among infecting Candida isolates, and MIC level was not associated with increased risk of death or NDI in this cohort of ELBW infants.

Association of participation in a supplemental nutrition program with stillbirth by race, ethnicity, and maternal characteristics

BACKGROUND

Participation in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) has been associated with lower risk of stillbirth. We hypothesized that such an association would differ by race/ethnicity because of factors associated with WIC participation that confound the association.

METHODS

We conducted a secondary analysis of the Stillbirth Collaborative Research Network's population-based case-control study of stillbirths and live-born controls, enrolled at delivery between March 2006 and September 2008. Weighting accounted for study design and differential consent. Five nested models using multivariable logistic regression examined whether the WIC participation/stillbirth associations were attenuated after sequential adjustment for sociodemographic, health, healthcare, socioeconomic, and behavioral factors. Models also included an interaction term for race/ethnicity x WIC.

RESULTS

In the final model, WIC participation was associated with lower adjusted odds (aOR) of stillbirth among non-Hispanic Black women (aOR: 0.34; 95% CI 0.16, 0.72) but not among non-Hispanic White (aOR: 1.69; 95% CI: 0.89, 3.20) or Hispanic women (aOR: 0.91; 95% CI 0.52, 1.52).

CONCLUSIONS

Contrary to our hypotheses, control for potential confounding factors did not explain disparate findings by race/ethnicity. Rather, WIC may be most beneficial to women with the greatest risk factors for stillbirth. WIC-eligible, higher-risk women who do not participate may be missing the potential health associated benefits afforded by WIC.

Antecedents and Outcomes of Abnormal Cranial Imaging in Moderately Preterm Infants

OBJECTIVES

To describe the frequency and findings of cranial imaging in moderately preterm infants (born at 29^0/7-33^6/7 weeks of gestation) across centers, and to examine the association between abnormal imaging and clinical characteristics.

STUDY DESIGN

We used data from the Neonatal Research Network Moderately Preterm Registry, including the most severe early (≤28 days) and late (>28 days) cranial imaging. Stepwise logistic regression and CART analysis were performed after adjustment for gestational age, antenatal steroid use, and center.

RESULTS

Among 7021 infants, 4184 (60%) underwent cranial imaging. These infants had lower gestational ages and birth weights and higher rates of small for gestational age, outborn birth, cesarean delivery, neonatal resuscitation, and treatment with surfactant, compared with those without imaging (P < .0001). Imaging abnormalities noted in 15% of the infants included any intracranial hemorrhage (13.2%), grades 3-4 intracranial hemorrhage (1.7%), cystic periventricular leukomalacia (2.6%), and ventriculomegaly (6.6%). Histologic chorioamnionitis (OR, 1.47; 95% CI, 1.19-1.83), gestational age (0.95; 95% CI, 0.94-0.97), antenatal steroids (OR, 0.55; 95% CI, 0.41-0.74), and cesarean delivery (OR, 0.66; 95% CI, 0.53-0.81) were associated with abnormal imaging. The center with the highest rate of cranial imaging, compared with the lowest, had a higher risk of abnormal imaging (OR, 2.08; 95% CI, 1.10-3.92). On the classification and regression-tree model, cesarean delivery, center, antenatal steroids, and chorioamnionitis, in that order, predicted abnormal imaging.

CONCLUSION

Among the 60% of moderately preterm infants with cranial imaging, 15% had intracranial hemorrhage, cystic periventricular leukomalacia or late ventriculomegaly. Further correlation of imaging and long-term neurodevelopmental outcomes in moderately preterm infants is needed.

Delivery Room Resuscitation and Short-Term Outcomes in Moderately Preterm Infants

OBJECTIVES

To describe the frequency and extent of delivery room resuscitation and evaluate the association of delivery room resuscitation with neonatal outcomes in moderately preterm (MPT) infants.

STUDY DESIGN

This was an observational cohort study of MPT infants delivered at 29^0/7 to 33^6/7 weeks' gestational age (GA) enrolled in the Neonatal Research Network MPT registry. Infants were categorized into 5 groups based on the highest level of delivery room intervention: routine care, oxygen and/or continuous positive airway pressure, bag and mask ventilation, endotracheal intubation, and cardiopulmonary resuscitation including chest compressions and/or epinephrine use. The association of antepartum and intrapartum risk factors and discharge outcomes with the intensity of resuscitation was evaluated.

RESULTS

Of 7014 included infants, 1684 (24.0%) received routine care and no additional resuscitation, 2279 (32.5%) received oxygen or continuous positive airway pressure, 1831 (26.1%) received bag and mask ventilation, 1034 (14.7%) underwent endotracheal intubation, and 186 (2.7%) received cardiopulmonary resuscitation. Among the antepartum and intrapartum factors, increasing GA, any exposure to antenatal steroids and prolonged rupture of membranes decreased the likelihood of receipt of all levels of resuscitation. Infants who were small for GA (SGA) had increased risk of delivery room resuscitation. Among the neonatal outcomes, respiratory support at 28 days, days to full oral feeds and length of stay were significantly associated with the intensity of delivery room resuscitation. Higher intensity of resuscitation was associated with increased risk of mortality.

CONCLUSIONS

The majority of MPT infants receive some level of delivery room resuscitation. Increased intensity of delivery room interventions was associated with prolonged respiratory and nutritional support, increased mortality, and a longer length of stay.

Outcome of Preterm Infants with Transient Cystic Periventricular Leukomalacia on Serial Cranial Imaging Up to Term Equivalent Age

OBJECTIVE

To determine the outcome of preterm infants whose cystic periventricular leukomalacia "disappeared" on serial screening cranial imaging studies.

STUDY DESIGN

Infants ≤26 weeks of gestation born between 2002 and 2012 who had cranial imaging studies at least twice, the most abnormal study at <28 days of age and another closest to 36 weeks, were reviewed. The outcome of late death (after 36 weeks postmenstrual age) or neurodevelopmental impairment (NDI) in surviving infants at 18-26 months corrected age was compared between the infants with no cystic periventricular leukomalacia on both studies and cystic periventricular leukomalacia that disappeared (cystic periventricular leukomalacia at <28 days but not at 36 weeks), persisted (cystic periventricular leukomalacia on both studies), or appeared late (cystic periventricular leukomalacia only at 36 weeks). Predictors of NDI were evaluated by logistic regression.

RESULTS

Of 7063 eligible infants, 433 (6.1%) had cystic periventricular leukomalacia. Among the 433 infants with cystic periventricular leukomalacia, cystic periventricular leukomalacia disappeared in 76 (18%), persisted in 87 (20%), and 270 (62%) had late cystic periventricular leukomalacia. Loss to follow-up ranged between 3% and 13%. Death or NDI was more common in infants with disappeared cystic periventricular leukomalacia compared with those with no cystic periventricular leukomalacia (38 of 72 [53%] vs 1776 of 6376 [28%]; OR [95% CI] 2.8 [1.8-4.6]). Disappeared, persistent, and late cystic periventricular leukomalacia were all also independently associated with NDI (OR 1.17, 1.21, and 1.16, respectively).

CONCLUSIONS

Infants with "disappeared" cystic periventricular leukomalacia are at increased risk of adverse outcome similar to infants with persistent or late cystic periventricular leukomalacia.

Mortality and pulmonary outcomes of extremely preterm infants exposed to antenatal corticosteroids

BACKGROUND

Antenatal corticosteroids are given primarily to induce fetal lung maturation but results from meta-analyses of randomized controlled trials have not shown mortality or pulmonary benefits for extremely preterm infants although these are the infants most at risk of mortality and pulmonary disease.

OBJECTIVE

We sought to determine if exposure to antenatal corticosteroids is associated with a lower rate of death and pulmonary morbidities by 36 weeks' postmenstrual age.

STUDY DESIGN

Prospectively collected data on 11,022 infants 22 0/7 to 28 6/7 weeks' gestational age with a birthweight of ≥401 g born from Jan. 1, 2006, through Dec. 31, 2014, were analyzed. The rate of death and the rate of physiologic bronchopulmonary dysplasia by 36 weeks' postmenstrual age were analyzed by level of exposure to antenatal corticosteroids using models adjusted for maternal variables, infant variables, center, and epoch.

RESULTS

Infants exposed to any antenatal corticosteroids had a lower rate of death (2193/9670 [22.7%]) compared to infants without exposure (540/1302 [41.5%]) (adjusted relative risk, 0.71; 95% confidence interval, 0.65-0.76; P < .0001). Infants exposed to a partial course of antenatal corticosteroids also had a lower rate of death (654/2520 [26.0%]) compared to infants without exposure (540/1302 [41.5%]); (adjusted relative risk, 0.77; 95% confidence interval, 0.70-0.85; P < .0001). In an analysis by each week of gestation, infants exposed to a complete course of antenatal corticosteroids had lower mortality before discharge compared to infants without exposure at each week from 23-27 weeks' gestation and infants exposed to a partial course of antenatal corticosteroids had lower mortality at 23, 24, and 26 weeks' gestation. Rates of bronchopulmonary dysplasia in survivors did not differ by antenatal corticosteroid exposure. The rate of death due to respiratory distress syndrome, the rate of surfactant use, and the rate of mechanical ventilation were lower in infants exposed to any antenatal corticosteroids compared to infants without exposure.

CONCLUSION

Among infants 22-28 weeks' gestational age, any or partial antenatal exposure to corticosteroids compared to no exposure is associated with a lower rate of death while the rate of bronchopulmonary dysplasia in survivors did not differ.