The effect of single or multiple courses of antenatal corticosteroid therapy on neonatal respiratory distress syndrome in singleton versus twin pregnancies.
BACKGROUND
Antenatal corticosteroid (ACS) treatment is widely used for the prevention of respiratory distress syndrome (RDS) in preterm infants. However, the efficacy and safety of ACS treatment remains controversial in twin pregnancies.


OBJECTIVE
To investigate the effect of ACS therapy, single or multiple courses, on the incidence of neonatal RDS in singleton and twin pregnancies.


METHODS
We retrospectively evaluated the pregnancy and neonatal outcomes of 450 singleton and 117 twin pregnancies delivered at 24-34 weeks of gestation due to preterm labour or preterm premature rupture of membranes. The subjects were categorised into four groups according to ACS exposure: 0, 1, 2 and > or = 3 courses.


RESULTS
Overall, RDS occurred more frequently in twins compared to singletons (41.0% vs 25.3%, P < 0.001). In singleton pregnancy, the incidence of RDS was significantly lower in the ACS user groups than in the non-user group, with the lowest incidence in the multiple course groups. An increase in the number of courses of ACS was associated with a reduction in the incidence of RDS (odds ratio 0.349, 95% confidence interval 0.226, 0.537, P < 0.001) independent of confounding variables. In twin pregnancies, however, the incidence of RDS was not significantly different in comparisons among the four groups.


CONCLUSIONS
Multiple courses of ACS were associated with a significantly decreased risk of RDS in singleton pregnancies. However, the current standard dose or interval for ACS administration in singleton pregnancy, as either a single or multiple courses, did not reduce RDS in twins.
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Suk-Joo
SJ
Choi
Seung Eun
SE
Song
Eun Sung
ES
Seo
Soo-young
SY
Oh
Jong-Hwa
JH
Kim
Cheong-Rae
CR
Roh
D000305:Adrenal Cortex Hormones / Q000008:administration & dosage*; D004200:Diseases in Twins / Q000517:prevention & control*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011247:Pregnancy; D047928:Premature Birth; D011297:Prenatal Exposure Delayed Effects; D012127:Respiratory Distress Syndrome, Newborn / Q000517:prevention & control*; D014427:Twins
D000305:Adrenal Cortex Hormones