Antenatal corticosteroids for periviable birth
Section snippets
Biologic plausibility for efficacy of antenatal corticosteroids in the periviable period
Antenatal corticosteroids work through multiple mechanisms to prepare the fetal lung for air breathing. The most well-known of these mechanisms is the induction of proteins and enzymes, including increased tissue and alveolar surfactant production. However, there are a number of other important biochemical effects including accelerated antioxidant production and induction of beta-receptor expression in the alveolar cells.2., 3. An equally important effect of antenatal corticosteroids is the
Cohort studies of antenatal corticosteroids in the periviable period
Table 1 demonstrates the experience of the NICHD Neonatal Network evaluating neonatal morbidity and mortality at 22–25 weeks of gestation in steroid-exposed vs. nonsteroid-treated infants.1 The study demonstrated a significant reduction in mortality in exposed neonates born in weeks 23, 24, and 25. Neonates delivered at 22 weeks showed a reduced mortality rate, which did not meet statistical significance. Overall, an odds ratio of 0.5 (95% CI: 0.52–0.65) was demonstrated for neonates born in
Choice of antenatal steroid in the periviable period
Cohort studies have compared dexamethasone and betamethasone for periviable steroid treatment. A study, of infants weighing between 400 and 1500 g, from the Neonatal Network of betamethasone.6 The 18–22 month follow-up of these infants (birth weight 400–1000 g) evaluating neurodevelopmental outcomes showed reductions in most neurodevelopmental outcomes with betamethasone treatment compared to dexamethasone.7 This difference was found to only be statistically significant for deafness. This work
Conclusion
While further study would be beneficial, the information that we presently have strongly suggests that antenatal corticosteroids have value when given in the periviable period and should be offered when clinically appropriate. This benefit is clear from 23 weeks on. It is less certain whether they should be utilized at 22 weeks or less. Because of the uncertainty in gestational age prediction, it is suggested that they should be used at this gestational age if preterm birth appears to be
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Development and growth of the lung
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Cited by (40)
James: Neonatal RDS case study
2024, Journal of Neonatal NursingThe complex challenge of antenatal steroid therapy nonresponsiveness
2022, American Journal of Obstetrics and GynecologyCitation Excerpt :There are scant RCT data specifically for ANS use in extremely preterm infants, thus the size of possible benefits and risks is largely unknown. According to cohort study data, there do seem to be benefits of ANS use in periviable pregnancies.60 However, we should also note that non-ANS patients may have had clinical reasons for not being able to receive steroid treatment, and as such these ANS or nontreated groups may be biased.1
Periviable Premature Rupture of Membranes
2020, Obstetrics and Gynecology Clinics of North AmericaAntenatal corticosteroids administration on mortality and morbidity in premature twins born at 25∼34 gestational weeks: A retrospective multicenter study
2020, European Journal of Obstetrics and Gynecology and Reproductive BiologyCitation Excerpt :Since Liggins and Howie first described improved survival and reduced morbidity among preterm infants treated with antenatal corticosteroids in 1972, their use has become internationally recommended practice [25,26]. Antenatal corticosteroids induce multipleorgan maturation in the fetus through several mechanisms, including induction of proteins and enzymes, and they prepare the immature fetal lung to breathe air through increased tissue and alveolar surfactant production, which results in increased compliance and lung volume and decreased vascular permeability [27]. A 2017 Cochrane review of 30 randomized controlled trials (comprising 7774 women and 8158 infants) comparing treatment with ACS versus placebo in patients at risk for preterm birth before 34 weeks' gestation demonstrated a significant reduction in the risk of neonatal death, RDS and the need for respiratory support, IVH, NEC, and early-onset systemic infections [3].
The gestational effect of antenatal corticosteroids on respiratory distress syndrome in very low birth weight infants: A population-based study
2020, Journal of the Formosan Medical AssociationCitation Excerpt :By using a population-based retrospective analysis, our data showed significant decrease in surfactant use for VLBW infants with RDS at gestational age between 26 and 33 weeks. Recently, more and more studies focused on the extension of antenatal corticosteroids use for periviable birth.3,8,9,14 The largest cohort study conducted by Ehret et al. also demonstrated significantly higher survival and survival without major morbidities in infants at 22 through 25 weeks' gestation after receiving concordant antenatal corticosteroid therapy and postnatal life support.11
Antenatal corticosteroids prior to preterm birth: betamethasone or dexamethasone?
2019, The Lancet Child and Adolescent Health
This work has, in part, been supported by the Multicenter Maternal–Fetal Medicine Unit (MFMU) Research Network Grant: U10 HD040585.