Prenatal and perinatal determinants of lung health and disease in early life: A national heart, lung, and blood institute workshop report

Human lung growth and development begins with preconception exposures and continues through conception and childhood into early adulthood. Numerous environmental exposures (both positive and negative) can affect lung health and disease throughout life. Infant lung health correlates with adult lung function, but significant knowledge gaps exist regarding the influence of preconception, perinatal, and postnatal exposures on general lung health throughout life. On October 1 and 2, 2015, the National Heart, Lung, and Blood Institute convened a group of extramural investigators to develop their recommendations for the direction(s) for future research in prenatal and perinatal determinants of lung health and disease in early life and to identify opportunities for scientific advancement. They identified that future investigations will need not only to examine abnormal lung development, but also to use developing technology and resources to better define normal and/or enhanced lung health. Birth cohort studies offer key opportunities to capture the important influence of preconception and obstetric risk factors on lung health, development, and disease. These studies should include well-characterized obstetrical data and comprehensive plans for prospective follow-up. The importance of continued basic science, translational, and animal studies for providing mechanisms to explain causality using new methods cannot be overemphasized. Multidisciplinary approaches involving obstetricians, neonatologists, pediatric and adult pulmonologists, and basic scientists should be encouraged to design and conduct comprehensive and impactful research on the early stages of normal and abnormal human lung growth that influence adult outcome

An evaluation of the benefits and harms of antenatal corticosteroid treatment for women at risk of imminent preterm birth or prior to elective Caesarean-section: an individual participant data meta-analysis.:Study protocol

Background: Antenatal corticosteroid treatment (ACT) has been widely accepted as a safe, beneficial treatment which improves outcomes following preterm birth. It has been shown to reduce respiratory distress syndrome and neonatal mortality and is commonly used in threatened or planned preterm delivery, as well as prior to elective Caesarean-section at term. There are some concerns however, that in some cases, ACT is used in patients where clinical benefit has not been established, or may potentially increase harm. Many women who receive ACT do not deliver preterm and the long-term consequences of ACT treatment are unclear. This study aims to evaluate the benefits and harms of ACT using latest trial evidence to allow refinement of current practice. Methods: This study will compare ACT with placebo or non-treatment. Inclusion criteria are: Randomised Controlled Trials (RCT) comparing ACT vs. no ACT (with or without placebo) in all settings. Exclusion criteria are: non-randomised or quasi-randomised studies and studies comparing single vs. multiple courses of ACT. Main outcomes are to evaluate, for women at risk of preterm birth or undergoing planned Caesarean- section, the benefits and harms of ACT, on maternal, fetal, newborn, and long-term offspring health outcomes. The individual participant data (IPD) of identified RCTs will be collected and consecutively synthesised using meta-analysis with both a one-stage model where all IPD is analysed together and a two-stage model where treatment effect estimates are calculated for each trial individually first and thereafter pooled in a meta-analysis. Sub-group analysis will be performed to identify heterogeneous effects of ACT across predefined risk groups. Discussion: Co-opt is the Consortium for the Study of Pregnancy Treatments and aims to complete a robust evaluation of the benefits and harms of ACT. This IPD meta-analysis will contribute to this by allowing detailed interrogation of existing trial datasets. PROSPERO registration: CRD42020167312 (03/02/2020

Femur-Sparing Pattern of Abnormal Fetal Growth in Pregnant Women from New York City After Maternal Zika Virus Infection

BACKGROUND: Zika virus (ZIKV) is a mosquito-transmitted flavivirus, which can induce fetal brain injury and growth restriction following maternal infection during pregnancy. Prenatal diagnosis of ZIKV-associated fetal injury in the absence of microcephaly is challenging due to an incomplete understanding of how maternal ZIKV infection affects fetal growth and the use of different sonographic reference standards around the world. We hypothesized that skeletal growth is unaffected by ZIKV infection and that the femur length can represent an internal standard to detect growth deceleration of the fetal head and/or abdomen by ultrasound. OBJECTIVE: To determine if maternal ZIKV infection is associated with a femur-sparing pattern of intrauterine growth restriction (IUGR) through analysis of fetal biometric measures and/or body ratios using the INTERGROWTH-21st Project (IG-21) and World Health Organization Fetal Growth Chart (WHO-FGC) sonographic references. STUDY DESIGN: Pregnant women diagnosed with a possible recent ZIKV infection at Columbia University Medical Center after traveling to an endemic area were retrospectively identified and included if a fetal ultrasound was performed. Data was collected regarding ZIKV testing, fetal biometry, pregnancy and neonatal outcomes. The IG-21 and WHO-FGC sonographic standards were applied to obtain Z-scores and/or percentiles for fetal head, abdominal circumference (HC, AC) and femur length (FL) specific for each gestational week. A novel IG-21 standard was also developed to generate Z-scores for fetal body ratios with respect to femur length (HC:FL, AC:FL). Data was then grouped within clinically relevant gestational age strata (34 weeks) to analyze time-dependent effects of ZIKV infection on fetal size. Statistical analysis was performed using Wilcoxon signed-rank test on paired data, comparing either AC or HC to FL. RESULTS: A total of 56 pregnant women were included in the study with laboratory evidence of a confirmed or possible recent ZIKV infection. Based on the CDC definition for microcephaly after congenital ZIKV exposure, microcephaly was diagnosed in 5% (3/56) by both the IG-21 and WHO-FGC standards (HC Z-score ≤ -2 or ≤ 2.3%). Using IG-21, IUGR was diagnosed in 18% of pregnancies (10/56; AC Z-score ≤-1.3, <10%). Analysis of fetal size using the last ultrasound scan for all subjects revealed a significantly abnormal skewing of fetal biometrics with a smaller AC versus FL by either IG-21 or WHO-FGC (p<0.001 for both). A difference in distribution of fetal AC compared to FL was first apparent in the 24-27 6/7 week strata (IG-21, p=0.002; WHO-FGC, p=0.001). A significantly smaller HC compared to FL was also observed by IG-21 as early as the 28-33 6/7 week strata (IG-21, p=0.007). Overall, a femur-sparing pattern of growth restriction was detected in 52% of pregnancies with either an HC:FL or AC:FL fetal body ratio less than the 10th percentile (IG-21 Z-score ≤-1.3). CONCLUSIONS: An unusual femur-sparing pattern of fetal growth restriction was detected in the majority of fetuses with congenital ZIKV exposure. Fetal body ratios may represent a more sensitive ultrasound biomarker to detect viral injury in nonmicrocephalic fetuses that could impart long-term risk for complications of congenital ZIKV infection

Risk factors associated with prolonged neonatal intensive care unit stay after threatened late preterm birth*

Objective: To identify risk factors associated with neonatal intermediate or intensive care unit (NICU) stay ≥ 3 days among women with threatened late preterm birth (PTB). Study design: Secondary analysis of women with nonanomalous, singleton gestations enrolled in multicenter trial of betamethasone versus placebo for late PTB. Maternal and obstetric characteristics at time of presentation with threatened PTB were compared between those with and without NICU stay ≥3 days. Multivariable logistic regression identified risk factors for NICU stay ≥ 3 days. Result: Of 2795 eligible mother-neonate dyads, 962 (34%) had NICU stay ≥3 days. Gestational age and fetal growth restriction as the reason for threatened PTB had the strongest association with NICU stay ≥3 days in the final model (AUC 0.76). Conclusion: Maternal and obstetric characteristics at the time of admission for threatened late PTB should be considered when counseling patients about the probability of NICU stay ≥3 days

Risk of Uterine Rupture and Placenta Accreta With Prior Uterine Surgery Outside of the Lower Segment

Objective—Women with a prior myomectomy or prior classical cesarean delivery are often delivered early by cesarean due to concern for uterine rupture. Although theoretically at increased risk for placenta accreta, this risk has not been well quantified. Our objective was to estimate and compare the risks of uterine rupture and placenta accreta in women with prior uterine surgery. Methods—Women with prior myomectomy or prior classical cesarean delivery were compared to women with a prior low transverse cesarean to estimate rates of both uterine rupture and placenta accreta. Results—One hundred seventy-six women with a prior myomectomy, 455 with a prior classical cesarean delivery, and 13,273 women with a prior low transverse cesarean were evaluated. Mean gestational age at delivery differed by group (p0.99) or in the prior classical cesarean delivery group (0.88%, p=0.13). Placenta accreta occurred in 0% (95% CI 0-1.98%) of prior myomectomy compared with 0.19% in the low transverse cesarean group (p>0.99) and 0.88% in the prior classical cesarean delivery group (p=0.01 relative to low transverse cesarean). The adjusted OR for the prior classical cesarean delivery group (relative to low transverse cesarean) was 3.23 (1.11-9.39) for uterine rupture and 2.09 (0.69-6.33) for accreta. The frequency of accreta for those with previa was 11.1% for the prior classical cesarean delivery and 13.6% for low transverse cesarean groups (p>0.99=1.0). Conclusion—A prior myomectomy is not associated with higher risks of either uterine rupture or placenta accreta. The absolute risks of uterine rupture and accreta after prior myomectomy are low

Antenatal Betamethasone for Women at Risk for Late Preterm Delivery

Infants born at 34 to 36 weeks’ gestation (late preterm) have greater risks of adverse respiratory and other outcomes, than those born at 37 weeks gestation or later. It is not known whether betamethasone administered to women at risk for late preterm delivery decreases risks of neonatal morbidities

Reductions in commuting mobility correlate with geographic differences in SARS-CoV-2 prevalence in New York City.

SARS-CoV-2-related mortality and hospitalizations differ substantially between New York City neighborhoods. Mitigation efforts require knowing the extent to which these disparities reflect differences in prevalence and understanding the associated drivers. Here, we report the prevalence of SARS-CoV-2 in New York City boroughs inferred using tests administered to 1,746 pregnant women hospitalized for delivery between March 22nd and May 3rd, 2020. We also assess the relationship between prevalence and commuting-style movements into and out of each borough. Prevalence ranged from 11.3% (95% credible interval [8.9%, 13.9%]) in Manhattan to 26.0% (15.3%, 38.9%) in South Queens, with an estimated city-wide prevalence of 15.6% (13.9%, 17.4%). Prevalence was lowest in boroughs with the greatest reductions in morning movements out of and evening movements into the borough (Pearson R = -0.88 [-0.52, -0.99]). Widespread testing is needed to further specify disparities in prevalence and assess the risk of future outbreaks

Trends in receipt of single and repeat courses of antenatal corticosteroid administration among preterm and term births: A retrospective cohort study

Aim: To investigate trends in receipt and timing of antenatal corticosteroid (ACS) administration over a ten‐year interval. Methods: Retrospective cohort study of all live births from 2006 to 2015 occurring at a tertiary level teaching hospital in Adelaide, Australia. We analysed temporal trends in the receipt of single courses and repeat doses of ACSs, according to administration timing prior to birth. The main outcome measures were receipt of a single course of ACS and whether administration was ‘Optimal’ (≥24 h to <seven days) or ‘Suboptimal’ (<24 h OR ≥7 days) according to timing prior to birth, as well as administration of repeat doses. Results: Among 47 105 live births, 4191 (8.9%) received any ACS, while 1009 (2.1%) received at least one repeat dose. From 2006/7 to 2014/15, receipt of a single course (relative risk (RR) 1.33; 95%CI 1.21, 1.47) or repeat dose of ACS (RR 1.24; 95%CI 1.01, 1.55) increased. Among women giving birth between 23–34 weeks gestation, receipt of any ACS increased from 75 to 84%, while an optimally timed single course of ACS increased from 20.4 to 31.0% (RR 1.40; 95%CI 1.24, 1.87). From 2006/7 to 2014/15, the greatest increase in ACS administration was evident among infants born 35–36 and ≥37 weeks gestation by caesarean section (RR 1.94; 95%CI 1.48, 2.55 and RR 2.55; 95%CI 1.86, 3.50, respectively). Conclusions: While frequently used, less than half of ACS administration prior to preterm birth was optimally timed. The impact of suboptimal ACS timing on neonatal outcomes requires further investigation.Luke E. Grzeskowiak, Rosalie M. Grivell and Ben W. Mo

Low-dose betamethasone-acetate for fetal lung maturation in preterm sheep

BackgroundAntenatal steroids are standard of care for women who are at risk of preterm delivery; however, antenatal steroid dosing and formulation have not been evaluated adequately. The standard clinical 2-dose treatment with betamethasone-acetate+betamethasone-phosphate is more effective than 2 doses of betamethasone-phosphate for the induction of lung maturation in preterm fetal sheep. We hypothesized that the slowly released betamethasone-acetate component induces similar lung maturation to betamethasone-phosphate+betamethasone-acetate with decreased dose and fetal exposure.ObjectiveThe purpose of this study was to investigate pharmacokinetics and fetal lung maturation of antenatal betamethasone-acetate in preterm fetal sheep.Study designGroups of 10 singleton-pregnant ewes received 1 or 2 intramuscular doses 24 hours apart of 0.25 mg/kg/dose of betamethasone-phosphate+betamethasone-acetate (the standard of care dose) or 1 intramuscular dose of 0.5 mg/kg, 0.25 mg/kg, or 0.125 mg/kg of betamethasone-acetate. Fetuses were delivered 48 hours after the first injection at 122 days of gestation (80% of term) and ventilated for 30 minutes, with ventilator settings, compliance, vital signs, and blood gas measurements recorded every 10 minutes. After ventilation, we measured static lung pressure-volume curves and sampled the lungs for messenger RNA measurements. Other groups of pregnant ewes and fetuses were catheterized and treated with intramuscular injections of betamethasone-phosphate 0.125 mg/kg, betamethasone-acetate 0.125 mg/kg, or betamethasone-acetate 0.5 mg/kg. Maternal and fetal betamethasone concentrations in plasma were measured for 24 hours.ResultsAll betamethasone-treated groups had increased messenger RNA expression of surfactant proteins A, B, and C, ATP-binding cassette subfamily A member 3, and aquaporin-5 compared with control animals. Treatment with 1 dose of intramuscular betamethasone-acetate 0.125mg/kg improved dynamic and static lung compliance, gas exchange, and ventilation efficiency similarly to the standard treatment of 2 doses of 0.25 m/kg of betamethasone-acetate+betamethasone-phosphate. Betamethasone-acetate 0.125 mg/kg resulted in lower maternal and fetal peak plasma concentrations and decreased fetal exposure to betamethasone compared with betamethasone-phosphate 0.125 mg/kg.ConclusionA single dose of betamethasone-acetate results in similar fetal lung maturation as the 2-dose clinical formulation of betamethasone-phosphate+betamethasone-acetate with decreased fetal exposure to betamethasone. A lower dose of betamethasone-acetate may be an effective alternative to induce fetal lung maturation with less risk to the fetus