REPEATED COURSES OF STEROIDS IN PRETERM MEMBRANE RUPTURE DO NOT INCREASE THE RISK OF HISTOLOGIC CHORIOAMNIONITIS

Antenatal administration of steroids (betamethasone 12 mg I.M. twice q 24 hr) enhances fetal lung maturation and reduces neonatal morbidity in preterm prelabor rupture of membranes (FROM). However, the risks of repeated administration of steroids 7 days after the initial course a re unknown. We evaluated the prevalence of histologic evidence of chor ioamnionitis in patients receiving single versus multiple courses of s teroids for fetal lung maturation. We performed a retrospective analys is of consecutive cases of preterm FROM at <32 weeks' gestation prospe ctively collected between July 1988 and March 1994. Obstetric and clin ical information were obtained for women who did not receive steroids for fetal lung maturity (n=55), those who received a single course (n= 47), and those with greater than or equal to 2 courses of steroids (n= 89). Placental pathology examination was performed after delivery, and histologic evidence of acute placental inflammation was determined an d scored semiquantitatively on a scale of 0-4, as previously described . Potential confounding, variables considered were: presence of oligoh ydramnios (vertical pocket of amniotic fluid II cm at ultrasound), ons et of labor prior to delivery, gestational age at delivery, and mode o f delivery. The three groups were comparable for gestational age at me mbrane rupture and at delivery, rate of oligohydramnios, labor prior t o delivery, and mode of delivery. Administration of multiple courses o f steroids was associated with a decrease in the rate of clinical chor ioamnionitis (p<0.0001) and severity of histologic acute placental inf lammation (mean +/-SD total score of acute inflammation: 10.7+/-7.2 vs . 7.3+/-6.0 vs. 6.9+/-6.0, p=0.005) compared with the groups receiving no steroids or administration of a single course of steroids. in pret erm FROM at <32 weeks, repeated administration of courses of steroids is not associated with an increase in the prevalence of clinical or hi stologic evidence of infectious outcome. These findings may reflect a greater likelihood for noninfected patients to remain quiescent and th us receive repeated courses of steroids.