Intravaginal clindamycin to reduce preterm birth in women with abnormal genital tract flora.

Objective: To assess the ability of clindamycin vaginal cream to reduce the incidence of preterm birth in women with abnormal genital tract flora in the second trimester of pregnancy.
Methods: This was a randomized, double-blind, placebo-controlled, tricenter study. A total of 409 women with abnormal genital tract flora on Gram stain of vaginal secretions at 13-20 weeks' gestation were randomized to receive a 3-day course of clindamycin vaginal cream or placebo. Those women who still had abnormal vaginal flora 3 weeks later received a 7-day course of the original study drug (ie, either clindamycin vaginal cream or placebo as per original randomization). The primary outcome measure was the incidence of preterm birth.
Results: There was a statistically significant reduction in the incidence of preterm birth in the clindamycin vaginal cream group (4%) compared with placebo (10%) (P <.03). Significantly more babies born preterm (63%) required admission to the neonatal intensive care unit compared with term infants (4%) (P <.001).
Conclusion: A 2% clindamycin vaginal cream, when compared with placebo administered to women with abnormal genital tract flora before 20 weeks' gestation, can reduce the incidence of preterm birth by 60% and hence the need for neonatal intensive care.