Should the sex of the fetus be considered when administering antenatal corticosteroids to preterm fetuses?

Abstract Aim We aimed to determine whether the effect of antenatal corticosteroids (ANS) differs in male and female fetuses without anomalies born before 32 weeks in terms of mortality and short‐term morbidity. Methods This single‐center retrospective study included infants born before 32 weeks' gestation and admitted to the neonatal intensive care unit between January 1, 2018, and December 31, 2020. Results The study included 210 infants with a median gestational age of 28.6 weeks (24–31.6), a birth weight of 1065 g (445–2165), and an ANS use rate of 80%. Compared to female fetuses exposed to ANS, male fetuses exposed to ANS had a lower mortality rate (23% and 11%, respectively, p = 0.038), but there were no differences in intraventricular hemorrhage, retinopathy of prematurity, necrotizing enterocolitis, respiratory distress syndrome, and APGAR scores of 1st and 5th but an increased rate of bronchopulmonary dysplasia (moderate/severe) ( p = 0.008). In addition, the mortality rate was similar in exposed and unexposed female fetuses ( p = 0.850). Enzyme activities and steroid levels in the placenta might be different in male and female fetuses, which could explain the results of ANS administration. Conclusions In our study, we have shown that ANS has no effect on mortality in female fetuses younger than 32 weeks. Future studies may focus on adjusting the administration of ANS based on fetal sex, altering the dose or taking fetal sex into account when performing ANS.