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

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.

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.

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).

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.