To Give or Not to Give Antenatal Corticosteroids in Late Preterm Twins

Background: Late preterm antenatal corticosteroids (ACS) in the late preterm period (34+0-36+6 weeks’ gestation) have been shown to  reduced respiratory morbidity in singleton pregnancies. The effects  of late preterm ACS in twin pregnancies are less well studied.

Objective: Our objective was to compare neonatal outcomes in late preterm twin pregnancies with and without exposure to ACS.

Materials and Methods:

Study design: Propensity score analysis using a large retrospective birth cohort.

Population: 940 twin pregnancies delivering at 34+0-36+6 weeks’ gestation (January 2017 - June 2024). 11 hospitals in the USA participating in a quality improvement program (OB COAP)

Intervention: One or more doses of ACS at  >=33 weeks’ gestation

Outcomes: Neonatal outcomes included respiratory complications, neonatal unit admission (NICU), and hypoglycemia. 

Statistical analysis: Propensity score analysis weighting for maternal, practitioner, hospital, and fetal/neonatal factors, including chorionicity, gestational age at birth, and birthweight.

Results: Of 940 twin pregnancies delivering late preterm, 602 (64.0%) were dichorionic and (326) 34.7% were monochorionic; 376 (40.1%) received ACS at >=33 weeks’ gestation.

Conclusions: Antenatal corticosteroids in twin pregnancies delivering at 34+0-36+6 weeks’ gestation were associated with a lower risk of respiratory complications but no differences in NICU admission or hypoglycemia.  More research is needed to determine the effects of late preterm steroids in twins by gestational week at delivery and after labour versus planned caesarean birth.