Antenatal Corticosteroids for the Prevention of Respiratory Distress Syndrome in Premature Twins

Antenatal corticosteroids and newborn respiratory outcomes in twins: A regression discontinuity study

OBJECTIVE

To estimate the effect of antenatal corticosteroids on newborn respiratory morbidity in twins.

DESIGN

Regression discontinuity applied to population-based birth registry data.

SETTING

British Columbia, Canada, 2008-2018.

POPULATION

Twin pregnancies admitted for birth between 31+0 and 36+6 weeks of gestation.

METHODS

During our study period, Canadian clinical practice guidelines recommended antenatal corticosteroid administration for imminent preterm birth up to 33+6 weeks. We used a logistic model to compare the predicted risks of our outcomes among pregnancies admitted for birth immediately before this clinical cut-point (higher probability of exposure to antenatal corticosteroids) versus immediately after it (lower probability).

MAIN OUTCOME MEASURES

Our primary outcome was a composite of newborn respiratory distress or in-hospital death. Our secondary outcome was a composite of newborn respiratory intervention or in-hospital death.

RESULTS

Among 2524 pregnancies (5035 liveborn twins), 47% of admissions before 34+0 weeks of gestation were exposed to antenatal corticosteroids but only 4.2% of admissions after this cut-point were exposed. The risk of newborn respiratory distress or in-hospital mortality increased abruptly at 34+0 weeks, corresponding to a protective effect of treatment (risk ratio [RR] 0.69, 95% CI 0.53-0.90; risk difference [RD] -12 cases per 100 births, 95% CI -20 to -4.1). There was no clear evidence for or against an effect on newborn respiratory intervention or in-hospital death (RR 0.89, 95% CI 0.70-1.13; RD -4.2 per 100, 95% CI -13 to +4.2).

CONCLUSIONS

Our findings provide evidence for the effectiveness of antenatal corticosteroids in preventing adverse newborn respiratory outcomes in twins.

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 antenatal corticosteroids on neonatal outcomes in twin and singleton pregnancies: a Korean national cohort study

OBJECTIVE

To investigate whether effects of antenatal corticosteroids on neonatal outcomes in preterm infants with very low birth weight were different by plurality.

DESIGN

Nationwide prospective cohort study.

PATIENTS

Twins and singletons with very low birth weight (<1500 g) who were born between 23+0 and 33+6 weeks of gestation and registered in the Korean Neonatal Network from January 2014 to December 2019.

MAIN OUTCOME MEASURES

Morbidity and mortality before discharge from neonatal intensive care unit.

RESULTS

Among a total of 9531 preterm infants with very low birth weight, there were 2364 (24.8%) twins and 7167 (75.2%) singletons. While 83.9% of singletons were exposed to at least one dose of antenatal corticosteroids, so were 87.9% of twins.Interaction analysis demonstrated that there was no significant difference in the effect of antenatal corticosteroids on morbidities or mortality between twins and singletons in either gestational age group (23-28 weeks or 29-33 weeks).Antenatal corticosteroids significantly decreased the risk of surfactant use (adjusted relative risk (aRR): 0.972 (95% CI: 0.961 to 0.984)), high-grade intraventricular haemorrhage (aRR: 0.621 (95% CI: 0.487 to 0.794)), periventricular leucomalacia (aRR: 0.728 (95% CI: 0.556 to 0.954)) and mortality (aRR: 0.758 (95% CI: 0.679 to 0.846)) in the gestational age group of 23-28 weeks. In the gestational age group of 29-33 weeks, antenatal corticosteroids significantly decreased the risk of surfactant use (aRR: 0.914 (95% CI: 0.862 to 0.970)) and mortality (aRR: 0.409 (95% CI: 0.269 to 0.624)) but increased the risk of sepsis (aRR: 1.416 (95% CI: 1.018 to 1.969)).

CONCLUSION

This study demonstrates that effect of antenatal corticosteroids on neonatal outcomes of preterm infants with very low birth weight does not differ significantly by plurality (twin or singleton pregnancy).

A case-control study on the effects of incomplete, one, and more than one dexamethasone course on acute respiratory problems in preterm neonates born between 280 and 366 weeks of gestation

OBJECTIVE

To compare the effects of an incomplete course and more than 1 course of dexamethasone, relative to a control of a single complete course, on foetal respiratory problems and other adverse outcomes of preterm birth.

METHODS

This was a retrospective chart review of 1800 women with preterm delivery. Data were collected on newborns whose mothers administered 1 full course of dexamethasone (916/1800; 50.9%), a partial course (716/1800; 39.8%) and more than 1 course (168/1800; 9.3%). Demographic data and adverse maternal and neonatal outcomes were recorded.

RESULTS

Preterm singleton newborns whose mothers received several steroid hormone courses were significantly more likely to have adverse outcomes than newborns of mothers given 1 course. The negative outcomes were the need for positive pressure ventilation ([aOR] 1.831; 95% CI, (1.185,2.829); P = 0.019), ventilator support ([aOR] 1.843; 95% CI, (1.187,2.861); P = 0.011), and phototherapy ([aOR] 1.997; 95% CI, (1.378,2.895); P <  0.001), transient tachypnoea of the newborn ([aOR] 1.801; 95% CI, (1.261,2.571); P = 0.002), intraventricular haemorrhage ([aOR] 2.215; 95% CI, (1.159, 4.233); P = 0.027), sepsis ([aOR] 1.737; 95% CI, (1.086, 2.777); P = 0.007), and admission to neonatal intensive care ([aOR] 1.822; 95% CI, (1.275,2.604); P = 0.001). In the group of very preterm infants, newborns of mothers administered an incomplete course had developed respiratory distress syndrome (RDS) ([aOR] 3.177; 95% CI, (1.485, 6.795); P = 0.006) and used ventilatory support ([aOR] 3.565; 95% CI, (1.912, 6.650); P <  0.001) more than those of mothers receiving a single course.

CONCLUSIONS

Preterm singleton newborns whose mothers were given multiple courses of dexamethasone had an increased incidence of RDS and other adverse outcomes than those of mothers receiving a full course. However, very preterm newborns whose mothers were administered 1 full dexamethasone course had a significantly lower incidence of RDS than those whose mothers were given partial courses.

Prediction of Neonatal Respiratory Morbidity Assessed by Quantitative Ultrasound Lung Texture Analysis in Twin Pregnancies

The objective of this study was to evaluate the performance of quantitative ultrasound of fetal lung texture analysis in predicting neonatal respiratory morbidity (NRM) in twin pregnancies. This was an ambispective study involving consecutive cases. Eligible cases included twin pregnancies between 27.0 and 38.6 weeks of gestation, for which an ultrasound image of the fetal thorax was obtained within 48 h of delivery. Images were analyzed using quantusFLM^® version 3.0. The primary outcome of this study was neonatal respiratory morbidity, defined as the occurrence of either transient tachypnea of the newborn or respiratory distress syndrome. The performance of quantusFLM^® in predicting NRM was analyzed by matching quantitative ultrasound analysis and clinical outcomes. This study included 166 images. Neonatal respiratory morbidity occurred in 12.7% of cases, and it was predicted by quantusFLM^® analysis with an overall sensitivity of 42.9%, specificity of 95.9%, positive predictive value of 60%, and negative predictive value of 92.1%. The accuracy was 89.2%, with a positive likelihood ratio of 10.4, and a negative likelihood ratio of 0.6. The results of this study demonstrate the good prediction capability of NRM in twin pregnancies using a non-invasive lung texture analysis software. The test showed an overall good performance with high specificity, negative predictive value, and accuracy.

Comparison of respiratory distress syndrome amongst preterm twins (28-34 Weeks) born within and after two weeks of completion of single antenatal corticosteroid course: A bidirectional cohort study

BACKGROUND

The literature on neonatal outcomes in preterm twins delivered before 34 weeks but within and after 14 days of a single initial steroid course is limited.

MATERIAL AND METHODS

This bidirectional (226 prospective and 42 retrospectives) cohort study was performed at a tertiary care teaching hospital in South India. We compared the respiratory distress syndrome and neonatal death amongst preterm twins from 28 to 34 weeks born < 14 days (Group A, n=268) and after 14 days (Group B, n=268) of completion of a single course of antenatal steroids. We used multivariable regression analysis (log-binomial model) to adjust for confounding variables. We generated a propensity-matched score with probit regression to analyse outcomes (respiratory distress and neonatal deaths).

RESULTS

The two groups had significant differences in the distribution of birthweight, gestation period and mode of delivery. On adjusted analysis, the period of gestation below 33 weeks and weight below 1.5 kg had the maximum influence on respiratory and other morbidities, and weight less than 1 kg on neonatal death. [adjusted relative risk (ARR) 26.06, (95%CI=2.37-285.5), p=0.008]. On propensity scoring after matching all these variables, we found an [ARR of 2.0 (95% CI: 1.03-3.88), P=0.017] for neonatal death after 14 days of steroid injection. The ARR for respiratory distress syndrome was 1.13 in those born after 14 days of steroids, though it did not reach statistical significance.

CONCLUSION

On propensity scoring, the steroid-delivery interval more than 14 days was associated with a significantly increased risk (ARR of 2) of neonatal death.

Association between antenatal corticosteroids use and perinatal mortality among preterm singletons and twins in Mwanza, Tanzania: an observational study

OBJECTIVES

To examine the association between antenatal corticosteroids (ACS) use and perinatal mortality in singletons and twins delivered before 35 weeks of gestation.

DESIGN

Secondary analysis of data from an observational prospective chart review study that investigated if exposure to ACS was associated with lower rates of perinatal mortality in preterm infants.

SETTING

This study was conducted in four hospitals located in Mwanza region, Tanzania.

PARTICIPANTS

The study population included all preterm singletons and twins delivered at these hospitals between 24 weeks 0 days and 34 weeks 6 days of gestation from July 2019 to February 2020.

OUTCOME MEASURES

The primary outcome was perinatal mortality; the secondary outcome was respiratory distress syndrome (RDS).

RESULTS

The study included 844 singletons and 210 twin infants. Three hundred and fourteen singletons (37.2%) and 52 twins (24.8%) were exposed to at least one dose of ACS. Adjusted multivariate analyses revealed that among singletons' exposure to ACS was significantly associated with a lower likelihood of perinatal mortality, adjusted relative risk (aRR) 0.30 (95% CI 0.22 to 0.40) and RDS, aRR 0.92 (95% CI 0.87 to 0.97). In twin infants, exposure to ACS was associated with a reduced risk of RDS only, aRR 0.87 (95% CI 0.78 to 0.98).

CONCLUSION

The use of ACS between 24 weeks 0 days and 34 weeks 6 days of gestation in both singletons and twins in low-resource settings is associated with positive infant outcomes. No adverse effects were noted. Further research that examines the benefits of ACS for twin infants is needed.

Dosage escalation of antenatal steroids in preterm twin pregnancies does not improve long-term outcome

OBJECTIVES

To analyze long-term effects of antenatal betamethasone (≤16 mg, =24 mg and >24 mg) in preterm twins on infant and childhood morbidity.

METHODS

Retrospective cohort study among 198 preterm twins. Three follow up time points, including a total of 84 outcomes, were evaluated: first neonatal examination after birth and in the neonatal period up to 10 days after birth using data from the clinic charts; examination from the 21st to the 24th month of life and examination from the 60th to the 64th months, using data from copies of the children's examination booklets sent back by the parents. Dosage-dependent and sex-specific long-term effects of antenatal betamethasone treatment on neonatal, infant and early childhood development and morbidity up to 5.3 years of age were analyzed.

RESULTS

Dosage escalation of >24 mg was not associated with improved neonatal, infant or early child hood outcome, independent of twin pair structure. In contrast, higher doses >24 mg were significantly linked to increased rates of congenital infections (OR 5.867, 95% CI 1.895-18.167). Male sex as a factor was obvious for lower rates of apnea-bradycardia-syndrome in neonates, higher rates of no free steps after 15 months in infancy and highest rates of motor clumsiness in early childhood.

CONCLUSIONS

Betamethasone dosage escalation >24 mg in twins born between 23⁺⁵ and 33⁺⁶ weeks of gestation did not improve neonatal, infant or early childhood morbidity. In contrast, higher doses >24 mg total dose resulted in significantly higher rates of congenital infections and are not recommended. For males, 24 mg betamethasone appears to be the preferable dose.

Evaluation of the effectiveness of antenatal corticoid in preterm twin and single pregnancies: a multicenter cohort study

BACKGROUND

The effects of antenatal corticosteroids (ANSs) on twins are not well established.

OBJECTIVE

To determine the impact of ANS use according to the number of fetuses.

METHODS

Retrospective cohort study of newborns between 23 and 33 weeks of gestational age, birth weight from 400 to 1499 g, without malformations, delivered at 20 public university hospitals from 2010 to 2014.Exposed group: Received ANS (any time, any dose) and no exposed group: no received ANS. Analysis of birth conditions and clinical outcomes. Association of variables, relative risks, and 95% confidence intervals estimated from the adjustment of log-binomial regression models.

RESULTS

About 7165 premature infants were analyzed: 5167 singleton, 937 twins, and 104 triplets. Characteristics of gestations with one, two, or three fetuses not receiving ANS were similar. Reduced hemodynamic instability in single and twins gestations in the first 72 h were observed (Adj R² Twins = 0.78; 95% CI = 0.69-0.86) (Adj R² Singles = 0.79; 95% CI = 0.62-0.99). Reduced peri-intraventricular hemorrhage (Adj R² Twins = 0.54; 95% CI = 0.36-0.78) (Adj R² singles = 0.54; 95% CI = 0.36-0.78); and early sepsis reduction on single and triplex gestations (Adj R² triplex = 0.51; 95% CI = 0.27-0.94) (Adj single R² = 0.51; 95% CI = 0.27-0.94) were observed.

CONCLUSIONS

This study demonstrates ANS produces an important protective factor for severe intraventricular hemorrhage and hemodynamic instability in single and multiple pregnancies. ANS had a protective effect on death and birth conditions improvement just in single gestations. Regarding respiratory aspects was not observed the protective effect in the single or multiple gestations.

Controversies in the management of twin pregnancy

Despite many advances in antenatal care, twin pregnancies still experience more adverse outcomes, in particular perinatal morbidity and mortality. They also pose a multitude of challenges and controversies, as outlined in this Review. Moreover, they are less likely to be included in clinical trials. Many issues on classification and management remain under debate. Efforts at standardizing diagnostic criteria, monitoring protocols, management and outcome reporting are likely to reduce their perinatal risks. The top 10 most important research uncertainties related to multiple pregnancies have been identified by both clinicians and patients. More robust research in the form of randomized trials and large well-conducted prospective cohort studies is needed to address these controversies. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Does antenatal steroids treatment in twin pregnancies prior to late preterm birth reduce neonatal morbidity? Evidence from a retrospective cohort study

PURPOSE

To evaluate whether antenatal corticosteroids (ACS) administration during the late-preterm (LPT) period in twin pregnancies is associated with decreased rate of neonatal morbidity.

METHODS

A retrospective cohort study including a total of 290 women with twin pregnancies resulting in live births of 580 neonates who delivered during LPT period between 2016 and 2018 at a tertiary medical center. Patients were allocated into two groups according to ACS exposure. Obstetric and neonatal outcomes were compared between the groups. Primary outcome was neonatal composite respiratory morbidity, defined as the occurrence of at least one of the followings: RDS, TTN, O2 requirement, CPAP use or mechanical ventilation.

RESULTS

Patients exposed to ACS were older and more commonly complicated by gestational diabetes compared to the non-exposed group. Moreover, women exposed to ACS delivered earlier (35.6 vs. 36.3 weeks, P < 0.001) and more frequently by cesarean section (76.4% vs. 54.1%, P = 0.002) compared to the non-exposed group. The rate of composite respiratory morbidity did not differ between the groups. Nevertheless, neonates exposed to ACS had higher rates of neonatal intensive care unit (NICU) admission and hypoglycemia compared to neonates without prior ACS exposure (27.8% vs. 11.7%, P = 0.001; 49.3% vs. 27.1%, P < 0.001, respectively). Multivariable logistic regression revealed that gestational age at delivery was the sole independent risk factor for NICU admission, whereas late-preterm ACS exposure was the only risk factor for hypoglycemia.

CONCLUSION

LPT-ACS administration in twin pregnancies complicated by LPT birth in our study did not reduce neonatal respiratory morbidity but was associated with higher rates of hypoglycaemia.

Controversies in antenatal corticosteroid treatment

Antenatal corticosteroids are now established as one of the cornerstones of therapy in the prevention of neonatal morbidity and mortality prior to preterm birth. Although this practice is widely accepted, a significant number of controversies exist. This review explores the knowledge gaps regarding the use of antenatal corticosteroids in the preterm, late preterm and term populations. Furthermore, the role of antenatal corticosteroids in special populations, such as diabetes, multiple pregnancies and periviable gestations, where high-quality data from randomized controlled trials are lacking, is also considered.

Effects of antenatal corticosteroids in twin neonates with late preterm birth (ACTWIN [Antenatal Corticosteroids in TWIN late preterm neonates] trial): study protocol for a randomized controlled trial

BACKGROUND

Antenatal corticosteroids have been proven to prevent adverse outcomes including respiratory morbidities in preterm neonates before 34 weeks of gestation. Recently, it has been suggested that antenatal corticosteroids may also be effective in singleton late preterm pregnancies, and guidelines recommend the use of corticosteroids in singleton pregnant women who are at risk for late preterm birth. On the contrary, there is a paucity of information regarding the effectiveness of corticosteroids in twin neonates with late preterm birth. This study aims to determine the effectiveness of antenatal corticosteroids in late preterm twin neonates.

METHODS

In this multicentre randomized controlled trial, women who are at risk for late preterm birth will be enrolled at 34 0/7 to 36 5/7 weeks of gestation. The participants will be randomly assigned to receive antenatal corticosteroids (betamethasone 12 mg, 3 mL intramuscularly [IM]) or placebo (normal saline 3 mL IM). The perinatal outcomes will be compared between the two groups of cases. The primary outcome is severe respiratory complications (the use of continuous positive airway pressure or high-flow nasal cannula for at least 12 h, supplemental oxygen administration with a fraction of oxygen 0.3 or more for at least 24 h, mechanical ventilation, or extracorporeal membranes oxygenation) or perinatal death within the first 72 h of delivery. The secondary outcomes are neonatal mortality and/or other neonatal morbidities.

DISCUSSION

This study will be the first randomized controlled trial that evaluates the effectiveness of antenatal corticosteroids in late preterm twin neonates.

TRIAL REGISTRATION

NCT03547791 (ClinicalTrials.gov), first submitted date: March 29, 2018, first posted date: June 6, 2018 (retrospectively registered).

Neonatal outcomes of antenatal corticosteroids in preterm multiple pregnancies compared to singletons

BACKGROUND

Antenatal corticosteroids (ACS) during preterm labour reduce neonatal mortality and morbidity. Evidence on preterm multiple pregnancies is limited and contradictory.

OBJECTIVE

Compare the effect of ACS on very low birth weight infant's (VLBW) mortality and morbidity among singleton and multiple pregnancies.

STUDY DESIGN

Retrospective cohort study, employing prospectively collected data, of infants 23 to 34 weeks' gestation and 500 to 1500 g born at the Neocosur Neonatal Network centers during 2007-2016. Neonatal outcomes were compared among singleton and multiple pregnancies exposed to at least one dose of ACS to those not exposed using logistic regression analyses controlled for birthweight, gestational age, sex, small for gestational age (SGA) and mode of delivery.

RESULTS

A total of 13,864 infants were studied; 2948 multiple (21.3%) and 10,904 singleton pregnancies (78.7%). Overall, 11,218 (81.4%) received at least one dose of ACS with a significant reduction in the risk of death, RDS and grade III or IV IVH compared to those not exposed. Both singleton and multiple pregnancies exposed to ACS showed similar reduced risk of death (aRR 0.41 [95% CI, 0.36-0.47] vs. aRR 0.46 [95% CI, 0.34-0.64]). However, ACS were not associated with reduced odds of RDS (aRR 0.89 [95% CI, 0.66-1.23]) or grade III or IV IVH (aRR 0.99 [95% CI, 0.67-1.48]) in multiple pregnancies.

CONCLUSION

The benefit of administration of at least one dose of ACS in VLBW multiple and singleton pregnancies is comparable in terms of death. However, ACS showed no relevant impact in short-term morbidity in multiple pregnancies.

Antenatal Corticosteroids: Who Should We Be Treating?

Antenatal corticosteroids remain one of the crucial interventions in those at risk for imminent preterm birth. Therapeutic benefits include reducing major complications of prematurity such as respiratory distress syndrome, intraventricular hemorrhage, and necrotizing enterocolitis, as well as an overall decrease in neonatal deaths. Optimal reductions in neonatal morbidity and mortality require a thoughtful review of the timing of administration. In addition, a thorough understanding is required of which patients maximally benefit from this intervention in the management and counseling of those at risk for preterm birth.