Early prenatal treatment of BV with clindamycin does not prevent late miscarriage or premature labor (PREMEVA)

Reference

Subtil D, Brabant G, Tilloy E, et al. Early clindamycin for bacterial vaginosis in pregnancy (PREMEVA): a multicentre, double-blind, randomised controlled trial. Lancet 2018;392(10160):2171-2179.

Synopsis

These researchers randomized pregnant women at low risk of adverse pregnancy outcomes with confirmed bacterial vaginosis on self-collected samples into 3 groups: a single round of clindamycin 300 mg twice daily for 4 days (n = 943); clindamycin once a month for 3 months (n = 968); or placebo (n = 958). Women at high risk of poor outcomes were randomized to receive the single round of clindamycin 300 mg twice daily for 4 days (n = 122) or clindamycin once a month for 3 months (n = 114). For the most part, the risk stratification was based on a previous history of late miscarriage (16 to 22 weeks') or preterm delivery (22 to 36 weeks'). Using intention-to-treat analysis, the composite outcome of spontaneous late miscarriage (between 16 and 21 weeks') or spontaneous very preterm delivery (between 22 and 32 weeks'), regardless of whether the newborn baby was alive, occurred in 0.8% of women who took a single course of clindamycin, 1.5% of women who took 3 courses, and 1.0% of women who took placebo. These differences were not statistically significant. Additionally, there was no difference in secondary outcomes, such as hospitalization, premature rupture of membranes, chorioamnionitis, and so forth. Among women at high risk of adverse outcomes, there was no statistically significant difference in the rate of the composite outcome in women who took a single course of clindamycin (6.0%) compared with those who took 3 courses (4.4%). The rate of adverse effects--the most common of which were diarrhea and abdominal pain--was comparable among the treatment groups. Although the study was powerful enough to detect small differences in outcomes among the low-risk patients, it was probably too small to detect those differences among the high-risk women.