Compared with vaginal delivery, early-term cesarean section (CS) is associated with an increased risk of neonatal respiratory morbidity. Given the role of steroids in lung maturation in preterm labor, few studies have investigated their effects on early-term delivery. Therefore, this study aimed to investigate the effect of antenatal betamethasone on neonatal respiratory morbidity in early-term elective cesarean (37-38 weeks and 6 d).
This randomized clinical trial was conducted in Mahdieh Hospital in Tehran in 2017. Women with single pregnancy who were candidates for planned elective CS in 37-38 weeks and 6 d of gestation were randomly assigned to either betamethasone group (intramuscular injection of 12 mg of betamethasone in two doses with an interval of 24 h from the 37th week of gestation) or control group (routine treatment). Then, neonatal respiratory morbidities, hospitalization in NICU, and its cause and duration were recorded and compared between the two groups.
Of all, 16 neonates (7%) suffered from one or more respiratory morbidities, and there was no significant difference between the betamethasone and control groups (six cases (6%) and 10 cases (9%), respectively, p = .299). There was also no significant difference between betamethasone and control groups in terms of the frequency of respiratory morbidities at the gestational age of 37 and 38 weeks (p > .05). Grunting, retraction, or nasal flaring was the most common respiratory morbidity that was observed in 13 neonates (6%). We observed the need for CPAP in three neonates (1%), respiratory distress syndrome (RDS) in three neonates (1%), transient tachypnea of the newborn (TTN) in two neonates (1%), need for resuscitation at birth in one neonate (0.5%), and apnea in one neonate (0.5%). There was no significant difference between the two groups in terms of respiratory morbidities (p > .05). A total of 17 neonates (8%) were admitted to NICU; the number of neonates admitted to NICU was significantly lower in betamethasone group than in the control group (three neonates (7.2%) and 14 neonates (12.7%), respectively, p = .005). Respiratory distress in 11 neonates (5%), sepsis in two neonates (1%), and other cases in four neonates (2%) were the main reasons for NICU admission. The prevalence of respiratory distress, as a cause for admission, was significantly lower in the betamethasone group (p = .005).
The findings of this study showed that intramuscular injection of 12 mg of betamethasone in two doses, with an interval of 24 h, after 37 weeks of gestation in women undergoing early-term CS did not have a significant effect on respiratory morbidities in neonates. However, it decreased the frequency of admission to NICU, especially admission due to respiratory distress; it could indicate that the respiratory morbidities were less severe in betamethasone group than in the control group.