Evaluation of the effect of antenatal betamethasone on neonatal respiratory morbidities in late preterm deliveries (34-37 weeks)

Does the use of antenatal corticosteroids reduce respiratory morbidity in babies born in late preterm period?

BACKGROUND

The aim of this study is to determine the effectiveness of antenatal corticosteroid in reducing respiratory morbidity in babies born in the late preterm period.

METHODS

Two hundred and eighty-six pregnant women at risk of having a late preterm delivery were studied. One hundred and forty-three (143) served as the cases and were given 2 doses of 12 mg intramuscular dexamethasone 12 h apart, while 143 served as the controls and were given a similar quantity of placebo. The women were followed up prospectively and data were collected on the pregnant women and their newborns on a standardized form. The neonates were assessed for acute respiratory distress syndrome and transient tachypnea of the newborn based on clinical signs, symptoms, and chest x-ray results (when indicated). The primary outcome was the occurrence of neonatal respiratory morbidity.

RESULTS

The primary outcome occurred in 5 out of 130 infants (3.8%) in the dexamethasone group and 31 out of 122 (25.4%) in the placebo group (P value = 0.000003). Birth asphyxia, neonatal intensive care admission and need for active resuscitation at birth also occurred significantly less frequently in the dexamethasone group (P value 0.004, 0.009, 0.014 respectively). There were no significant group differences in the incidence of neonatal sepsis, neonatal jaundice, hypoglycemia and feeding difficulties.

CONCLUSIONS

Administration of dexamethasone to women at risk for late preterm delivery significantly reduced the rate of neonatal respiratory complications, neonatal intensive care unit admission, and need for active resuscitation at birth.

TRIAL REGISTRATION

PACTR ( www.pactr.org ) Registration Number: PACTR202304579281358. The study was retrospectively registered on April 19, 2023.

Antenatal Corticosteroid Treatment During the Late-Preterm Period and Neonatal Outcomes for Twin Pregnancies

Importance

Antenatal corticosteroid treatment of individuals with singletons at risk for delivery during the late-preterm period has been academically recommended. However, the evidence on the use of antenatal corticosteroid treatment for twins at risk for delivery during the late-preterm period is still lacking.

Objective

To evaluate whether antenatal corticosteroid treatment during the late-preterm period in twin pregnancies was associated with a lower risk of newborn morbidity.

Design, Setting, and Participants

This retrospective cohort study of twin pregnancies delivered from February 1, 2013, to September 30, 2020, in a university-affiliated hospital in China included 1974 individuals with twin pregnancies who were at risk for late preterm birth (34 weeks and 0 days to 36 weeks and 6 days of gestation). Data were analyzed from June 30 to July 13, 2023.

Exposures

Antenatal corticosteroid treatment during the late-preterm period.

Main Outcomes and Measures

The primary outcome measure was composite neonatal respiratory morbidity, defined as at least 1 of the following postnatal occurrences in at least 1 neonate of the twins: respiratory distress syndrome, mechanical ventilation, surfactant administration, transferred with respiratory complications, or neonatal death. Propensity score overlap weighting was used to analyze the association between antenatal corticosteroid treatment and the risk of neonatal outcomes.

Results

The study population consisted of 1974 individuals with twin pregnancies, including 303 (15.3%; mean [SD] maternal age, 30.8 [4.2] years) who received antenatal corticosteroid treatment and 1671 (84.7%; mean [SD] maternal age, 31.2 [4.0] years) who did not receive antenatal corticosteroid treatment. The propensity score overlap weighting showed no significant differences between the antenatal corticosteroid treatment group and the no-antenatal corticosteroid treatment group in the risk of neonatal primary outcome (29 of 303 [9.6%] vs 41 of 1671 [2.5%]; weighted odds ratio, 1.27 [95% CI, 0.60-2.76]). None of the subgroup interaction tests were significant for the neonatal primary outcome in terms of gestational age at delivery, year of delivery, chorionicity, at least 1 infant small for gestational age, intertwin growth discordance, and infant sex, and neither was the sensitivity analysis of using propensity score matching and a different administration-to-birth interval and treating twin infants as individuals.

Conclusions and Relevance

This cohort study found insufficient evidence that antenatal corticosteroid treatment during the late-preterm period in twin pregnancies could be associated with a lower risk of newborn morbidity. This new finding can provide a reference for clinical practice.

Effects of Single-Course Betamethasone on the Outcomes of Late Preterm Neonates

Background Prenatal glucocorticoids are commonly used in pregnancies before 34 weeks of gestation in women at risk of preterm delivery; however, the effects of these drugs on late preterm infants (those born after the 34th week of pregnancy) are controversial. As a result, we aimed to investigate the effect of a single course of betamethasone (two doses of betamethasone every 24 hours) on the neonatal outcome of late preterm births. Methods We retrospectively assessed all spontaneous late preterm births (34-36+6 weeks of gestation) at a tertiary hospital in Iran over a period of two and a half years. Exclusion criteria included multiple pregnancies, induced labor, and fetal malformations identified in sonograms. Neonatal outcome measures encompassed first and five-minute Apgar scores, respiratory distress syndrome, neonatal death, birth asphyxia, and the need for positive pressure ventilation, continuous positive airway pressure, tracheal intubation, and surfactant. Baseline characteristics, such as maternal age, parity, fetal gender, and high-risk pregnancy, were considered confounding variables. High-risk pregnancies were defined as any cases involving prolonged rupture of membranes or maternal comorbidities such as severe anemia, preeclampsia, diabetes, or COVID-19. Results During the study period, there were 830 spontaneous preterm births at our center. Of these, only 195 (23.5%) received complete doses of betamethasone. Low birth weight was more common in mothers who did not receive betamethasone compared to those who did (63.6% vs. 41.2%). The mean gestational age was lower in mothers who received betamethasone than in those who did not. Respiratory distress syndrome was more common in mothers who received betamethasone (P<0.001, RR 2.11, 95% CI (0.98-4.18)). However, after adjusting for confounding factors, such as gestational age and birth weight, betamethasone did not increase the risk of respiratory distress syndrome. Other adverse neonatal outcomes did not differ significantly. Conclusions There were no differences in neonatal outcomes between those who received betamethasone and those who did not.

The effect of time interval between antenatal corticosteroid administration and delivery on outcomes in late preterm neonates born to mothers with diabetes: a retrospective cohort study

Objectives

The study aims to investigate whether the time interval between administering antenatal corticosteroids (ACS) and delivery influences the neonatal outcomes in late preterm (LPT) neonates (34 + 0 to 36 + 6 weeks) born to mothers with diabetes.

Study design

This retrospective cohort study included women with any type of diabetes who gave birth between 34 + 0 weeks and 36 + 6 weeks of gestation. Based on the time interval between the first dose of corticosteroid and delivery, the cases were stratified into the following groups: <2, 2-7, and >7 days. Women unexposed to ACS served as the control group. The primary outcomes included the incidence of neonatal hypoglycemia and respiratory distress syndrome/transient tachypnea of the newborn. Multivariate logistic regression was used to assess the relationship between the time interval and neonatal outcomes and adjust for potential confounders.

Results

The study enrolled a total of 636 parturients. Among them, 247 (38.8%) delivered within 2 days after ACS administration, 169 (26.6%) within 2-7 days, and 126 (19.8%) at >7 days. Baseline characteristics such as type of diabetes, methods of glycemic control, preterm premature rupture of membrane, placenta previa, cesarean delivery, indication for delivery, percentage of large for gestational age, birth weight, and HbA1c in the second or third trimester were significantly different among the four groups. The multivariate analysis showed no statistically significant difference in the incidence of primary or secondary neonatal outcomes between the case and control groups.

Conclusions

ACS treatment was not associated with neonatal hypoglycemia and respiratory outcomes in LPT neonates born to diabetic mothers, regardless of the time interval to delivery.

Low-Cost SpO2 Integrated Neonatal CPAP Device for Low Resource Setting

Introduction

More than 60% of preterm births take place in South Asia and sub-Saharan Africa, making prematurity a primary cause of neonatal mortality. Even though continuous positive airway pressure (CPAP) is a popular treatment for respiratory distress syndrome (RDS) and is safe, practicable, and efficient for use in LMICs, it is crucial to ensure that neonates receive the full benefits of the therapy by monitoring their blood oxygen level.

Methods

A centrifugal fan, power source, control system, and sensors are all included in our design. A centrifugal fan was created to provide air at positive pressure in the range of approximately 4 cmH2O to 20 cmH2O utilizing revolving blades (impeller), a DC motor, and a fixed component. The control unit contains a microcontroller to handle sensor data. The proportional-integral (PI) controller board's external potentiometer is used to set the pressure level.

Results

To ascertain whether the prototype satisfies the design requirements, it was constructed and put through several iterations and testing. The proposed device's prototype was tested for accuracy, affordability, and usability. The centrifugal fan speed measurement was accurate to within 94.5%, while the oxygen concentration sensor reading was accurate to within 98.5%.

Conclusion

The design investigates viability of a straightforward, inexpensive, portable SpO2 integrated neonatal CPAP device for use in the delivery room in low-resource countries and to evaluates methods for measuring flows during CPAP treatment by monitoring the level of oxygen in the blood and pressure level delivered by the device using the lowest and safest setting that yields useful results.

Antenatal Corticosteroid Exposure is Associated with Childhood Mental Disorders in Late Preterm and Term Infants

OBJECTIVES

To study the association between antenatal corticosteroids treatment and childhood mental disorders in infants born at different gestational ages, and to investigate the effect of different administration timing.

STUDY DESIGN

This population-based cohort study used data from the Taiwan National Health Insurance Research Database. All singleton live births born between 2004 and 2010 were enrolled and followed up for at least 6 years. The primary outcome was any childhood mental disorder. Secondary outcomes included 7 specific subgroups of mental disorders.

RESULTS

A total of 1 163 443 singleton infants were included in the analysis, and 16 847 (1.45%) infants were exposed to antenatal corticosteroid treatment. Children exposed to antenatal corticosteroids were found to have a higher risk of developing childhood mental disorders in the entire cohort (hazard ratio [HR], 1.13; 95% CI, 1.08-1.18), the term group (HR, 1.11; 95% CI, 1.05-1.16), and the late-preterm group (HR, 1.15; 95% CI, 1.06-1.25). The administration of corticosteroids in the early stage of pregnancy (<28 weeks of gestation) significantly increased the risk of childhood mental disorders (HR, 1.22; 95% CI, 1.14-1.31).

CONCLUSIONS

Exposure to antenatal corticosteroid treatment increases the cumulative risk of childhood mental disorders and attention deficit hyperactivity disorders, both in term and late preterm infants. The administration of corticosteroids in the early stage of pregnancy tends to increase the risk of mental disorders.

Autophagy-related signaling pathways in non-small cell lung cancer

Lung cancer is one of the most prevalent causes of morbidity and mortality in both men and women across the globe. The disease has a quiet phenotype at first, which leads to chronic tumor development. Non-small cell lung cancer (NSCLC) is the most common kind of lung cancer, accounting for 85 percent of all lung malignancies. Autophagy has been described as an intracellular "recycle bin" where damaged proteins and molecules are degraded. Autophagy regulation is mainly dependent on signaling pathways such as phosphoinositide 3-kinases (PI3K), AKT, and the mammalian target of rapamycin (mTOR). In the context of NSCLC, studies on these signaling pathways are inconsistent, but our literature review suggests that the inhibition of mTOR, PI3K/AKT, and epidermal growth factor receptor signaling pathways by different medications can active autophagy and inhibit NSCLC progression. In conclusion, signaling pathways related to autophagy are effective therapeutic approaches for the treatment of NSCLC.

Comparison of neonatal outcomes with and without the administration of betamethasone in late preterm births

OBJECTIVE

To evaluate the effects of antenatal steroid administration on neonatal outcomes in late preterm births.

METHODS

Demographic and neonatal data from women who gave birth between May 2018 and March 2021 at 34⁺⁰ -36⁺⁶  weeks of gestation were screened from the information system of the hospital. The patients were assigned to two groups: those who were and those who were not given steroids. All parameters were compared between the two groups.

RESULTS

The 1-minute (9 versus 8) and 5-minute (10 versus 9) Apgar scores, need for a neonatal intensive care unit (NICU) stay (23.7% versus 27.8%), length of stay (Day) in the NICU (1.97 ± 0.24 versus 2.45 ± 0.16), rate of transient tachypnea of the newborn (3.3% versus 7.8%), respiratory distress syndrome (2.5% versus 5.2%), need for mechanical ventilation (1.2% versus 3.8%), and neonatal sepsis (1% versus 2.6%) were lower in the group that received betamethasone compared with the group that did not; the differences between the two groups were statistically significant.

CONCLUSION

Based on the results of the present study, we believe that antenatal steroid administration would be beneficial before late preterm births occurring between 34⁺⁰ and 36⁺⁶  weeks of pregnancy, considering the significant reduction in various respiratory complications, especially in respiratory distress syndrome and the need for an NICU stay.

Antenatal corticosteroids for impending late preterm (34-36+6 weeks) deliveries-A systematic review and meta-analysis of RCTs

Background

Administration of antenatal corticosteroids (ANC) for impending preterm delivery beyond 34 weeks of gestation continues to be a controversial issue despite various guidelines for obstetricians and gynaecologists.

Objective

To compare outcomes following exposure to ANC for infants born between 34–36⁺⁶ weeks’ gestation.

Methods

A systematic review of randomised controlled trials (RCT) reporting neonatal outcomes after ANC exposure between 34–36+6 weeks’ gestation using Cochrane methodology. Databases including PubMed, Embase, Emcare, Cochrane Central library and Google Scholar were searched in May 2020. Primary outcomes: (1) Need for respiratory support (Mechanical ventilation, CPAP, high flow) or oxygen (2) Hypoglycemia. Secondary outcomes included respiratory distress syndrome (RDS), transient tachypnoea of newborn (TTN), need for neonatal resuscitation at birth [only in the delivery room immediately after birth (not in neonatal intensive care unit (NICU)], admission to NICU, mortality and developmental follow up. Level of evidence (LOE) was summarised by GRADE guidelines.

Main results

Seven RCTs (N = 4144) with low to high risk of bias were included. Only one RCT was from high income countries, Meta-analysis (random-effects model) showed (1) reduced need for respiratory support [5 RCTs (N = 3844); RR = 0.68 (0.47–0.98), p = 0.04; I² = 55%; LOE: Moderate] and (2) higher risk of neonatal hypoglycaemia [4 RCTs (N = 3604); RR = 1.61(1.38–1.87), p<0.00001; I² = 0%; LOE: High] after ANC exposure. Neonates exposed to ANC had reduced need for resuscitation at birth. The incidence of RDS, TTN and surfactant therapy did not differ significantly. None of the included studies reported long-term developmental follow up.

Conclusions

Moderate quality evidence indicates that ANC exposure reduced need for respiratory support, and increased the risk of hypoglycaemia in late preterm neonates. Large definitive trials with adequate follow up for neurodevelopmental outcomes are required to assess benefits and risks of ANC in this population.

Antenatal corticosteroid therapy in late preterm delivery: a nationwide population-based retrospective study in Taiwan

OBJECTIVE

To investigate whether antenatal corticosteroid therapy improves neonatal and maternal outcomes in late preterm delivery.

DESIGN

Population-based retrospective study.

SETTING

The linkages of Taiwan's National Health Insurance Research Database, National Birth Reporting Database, and the Taiwan Maternal and Child Health Database.

POPULATION

All births at risk for late preterm deliveries in Taiwan between 2004 and 2011.

METHODS

For every birth at risk for late preterm delivery, five controls randomly matched by maternal and gestational ages and birthweight were included. A conditional logistic regression analysis was applied for risk estimation, with births without corticosteroids as the reference group. Odds ratios were adjusted for caesarean section, parity, sex, gestational hypertension and gestational diabetes mellitus.

MAIN OUTCOME MEASURES

Neonatal outcomes, maternal outcomes and the utilisation of healthcare services.

RESULTS

The outcomes of 5745 women treated with corticosteroids between 34⁺⁰  weeks and 36⁺⁶  weeks of gestation were compared with those of 28 135 untreated controls. Compared with the controls, births from women administered corticosteroids reduced the need for continuous positive airway pressure, the number of neonatal intensive care unit admission, and the need for glucose administration, as well as the risk of neonatal respiratory distress, but increased the risk of neonatal sepsis and the number of outpatient visits.

CONCLUSIONS

Antenatal corticosteroid therapy in women at risk of late preterm delivery may significantly reduce the need for respiratory support and glucose supply, and respiratory complication risk in neonates.

TWEETABLE ABSTRACT

Antenatal corticosteroids in late preterm delivery reduced the risk of neonatal respiratory complications in Taiwan.

Dexamethasone versus betamethasone for preterm birth: a systematic review and network meta-analysis

OBJECTIVE

This study aimed to evaluate the comparative clinical effectiveness and safety of dexamethasone vs betamethasone for preterm birth.

DATA SOURCES

The sources searched were MEDLINE, EMBASE, Cochrane Library, LILACS, ClinicalTrials.gov, and International Clinical Trials Registry Platform without language restrictions until October 2019 in addition to the reference lists of included studies. Field experts were also contacted.

STUDY ELIGIBILITY CRITERIA

Randomized or quasi-randomized controlled trials comparing any corticosteroids against each other or against placebo at any dose for preterm birth were included in the study.

METHODS

Three researchers independently selected and extracted data and assessed the risk of bias of the included studies by using Early Review Organizing Software and Covidence software. Random-effects pairwise meta-analysis and Bayesian network meta-analysis were performed. The primary outcomes were chorioamnionitis, endometritis or puerperal sepsis, neonatal death, respiratory distress syndrome, and neurodevelopmental disability.

RESULTS

A total of 45 trials (11,227 women and 11,878 infants) were included in the study. No clinical or statistical difference was found between dexamethasone and betamethasone in neonatal death (odds ratio, 1.05; 95% confidence interval, 0.62-1.84; moderate-certainty evidence), neurodevelopmental disability (odds ratio, 1.03; 95% confidence interval, 0.80-1.33; moderate-certainty evidence), intraventricular hemorrhage (odds ratio, 1.04; 95% confidence interval, 0.56-1.78); low-certainty evidence), or birthweight (+5.29 g; 95% confidence interval, -49.79 to 58.97; high-certainty evidence). There was no statistically significant difference, but a potentially clinically important effect was found between dexamethasone and betamethasone in chorioamnionitis (odds ratio, 0.70; 95% confidence interval, 0.45-1.06; moderate-certainty evidence), fetal death (odds ratio, 0.81; 95% confidence interval, 0.24-2.41; low-certainty evidence), puerperal sepsis (odds ratio, 2.04; 95% confidence interval, 0.72-6.06; low-certainty evidence), and respiratory distress syndrome (odds ratio, 1.34; 95% confidence interval, 0.96-2.11; moderate-certainty evidence). Meta-regression, subgroup, and sensitivity analyses did not reveal important changes regarding the main analysis.

CONCLUSION

Corticosteroids have proven effective for most neonatal and child-relevant outcomes compared with placebo or no treatment for women at risk of preterm birth. No important difference was found on neonatal death, neurodevelopmental disability, intraventricular hemorrhage, and birthweight between corticosteroids, and there was no statistically significant difference, but a potentially important difference was found in chorioamnionitis, fetal death, endometritis or puerperal sepsis, and respiratory distress syndrome. Further research is warranted to improve the certainty of evidence and inform health policies.

Antenatal corticosteroids for accelerating fetal lung maturation for women at risk of preterm birth

BACKGROUND

Respiratory morbidity including respiratory distress syndrome (RDS) is a serious complication of preterm birth and the primary cause of early neonatal mortality and disability. Despite early evidence indicating a beneficial effect of antenatal corticosteroids on fetal lung maturation and widespread recommendations to use this treatment in women at risk of preterm delivery, some uncertainty remains about their effectiveness particularly with regard to their use in lower-resource settings, different gestational ages and high-risk obstetric groups such as women with hypertension or multiple pregnancies. This updated review (which supersedes an earlier review Crowley 1996) was first published in 2006 and subsequently updated in 2017.

OBJECTIVES

To assess the effects of administering a course of corticosteroids to women prior to anticipated preterm birth (before 37 weeks of pregnancy) on fetal and neonatal morbidity and mortality, maternal mortality and morbidity, and on the child in later life.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (3 September 2020), ClinicalTrials.gov, the databases that contribute to the WHO International Clinical Trials Registry Platform (ICTRP) (3 September 2020), and reference lists of the retrieved studies.

SELECTION CRITERIA

We considered all randomised controlled comparisons of antenatal corticosteroid administration with placebo, or with no treatment, given to women with a singleton or multiple pregnancy, prior to anticipated preterm delivery (elective, or following rupture of membranes or spontaneous labour), regardless of other co-morbidity, for inclusion in this review.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane Pregnancy and Childbirth methods for data collection and analysis. Two review authors independently assessed trials for inclusion, assessed risk of bias, evaluated trustworthiness based on predefined criteria developed by Cochrane Pregnancy and Childbirth, extracted data and checked them for accuracy, and assessed the certainty of the evidence using the GRADE approach. Primary outcomes included perinatal death, neonatal death, RDS, intraventricular haemorrhage (IVH), birthweight, developmental delay in childhood and maternal death.

MAIN RESULTS

We included 27 studies (11,272 randomised women and 11,925 neonates) from 20 countries. Ten trials (4422 randomised women) took place in lower- or middle-resource settings. We removed six trials from the analysis that were included in the previous version of the review; this review only includes trials that meet our pre-defined trustworthiness criteria. In 19 trials the women received a single course of steroids. In the remaining eight trials repeated courses may have been prescribed. Fifteen trials were judged to be at low risk of bias, two had a high risk of bias in two or more domains and we ten trials had a high risk of bias due to lack of blinding (placebo was not used in the control arm. Overall, the certainty of evidence was moderate to high, but it was downgraded for IVH due to indirectness; for developmental delay due to risk of bias and for maternal adverse outcomes (death, chorioamnionitis and endometritis) due to imprecision. Neonatal/child outcomes Antenatal corticosteroids reduce the risk of: - perinatal death (risk ratio (RR) 0.85, 95% confidence interval (CI) 0.77 to 0.93; 9833 infants; 14 studies; high-certainty evidence; 2.3% fewer, 95% CI 1.1% to 3.6% fewer), - neonatal death (RR 0.78, 95% CI 0.70 to 0.87; 10,609 infants; 22 studies; high-certainty evidence; 2.6% fewer, 95% CI 1.5% to 3.6% fewer), - respiratory distress syndrome (RR 0.71, 95% CI 0.65 to 0.78; 11,183 infants; studies = 26; high-certainty evidence; 4.3% fewer, 95% CI 3.2% to 5.2% fewer). Antenatal corticosteroids probably reduce the risk of IVH (RR 0.58, 95% CI 0.45 to 0.75; 8475 infants; 12 studies; moderate-certainty evidence; 1.4% fewer, 95% CI 0.8% to1.8% fewer), and probably have little to no effect on birthweight (mean difference (MD) -14.02 g, 95% CI -33.79 to 5.76; 9551 infants; 19 studies; high-certainty evidence). Antenatal corticosteroids probably lead to a reduction in developmental delay in childhood (RR 0.51, 95% CI 0.27 to 0.97; 600 children; 3 studies; moderate-certainty evidence; 3.8% fewer, 95% CI 0.2% to 5.7% fewer). Maternal outcomes Antenatal corticosteroids probably result in little to no difference in maternal death (RR 1.19, 95% CI 0.36 to 3.89; 6244 women; 6 studies; moderate-certainty evidence; 0.0% fewer, 95% CI 0.1% fewer to 0.5% more), chorioamnionitis (RR 0.86, 95% CI 0.69 to 1.08; 8374 women; 15 studies; moderate-certainty evidence; 0.5% fewer, 95% CI 1.1% fewer to 0.3% more), and endometritis (RR 1.14, 95% CI 0.82 to 1.58; 6764 women; 10 studies; moderate-certainty; 0.3% more, 95% CI 0.3% fewer to 1.1% more) The wide 95% CIs in all of these outcomes include possible benefit and possible harm.

AUTHORS' CONCLUSIONS

Evidence from this updated review supports the continued use of a single course of antenatal corticosteroids to accelerate fetal lung maturation in women at risk of preterm birth. Treatment with antenatal corticosteroids reduces the risk of perinatal death, neonatal death and RDS and probably reduces the risk of IVH. This evidence is robust, regardless of resource setting (high, middle or low). Further research should focus on variations in the treatment regimen, effectiveness of the intervention in specific understudied subgroups such as multiple pregnancies and other high-risk obstetric groups, and the risks and benefits in the very early or very late preterm periods. Additionally, outcomes from existing trials with follow-up into childhood and adulthood are needed in order to investigate any longer-term effects of antenatal corticosteroids. We encourage authors of previous studies to provide further information which may answer any remaining questions about the use of antenatal corticosteroids without the need for further randomised controlled trials. Individual patient data meta-analyses from published trials are likely to provide answers for most of the remaining clinical uncertainties.

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: Study protocol for an individual participant data meta-analysis

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).