Dr. Roberto Romero, with Wayne State University/Hutzel Women’s Hospital in Detroit, Michigan, and colleagues point out that a number of systematic reviews have evaluated evidence concerning the treatment of abnormal genital tract infection in early pregnancy. “However,” they explain, “none of these systematic reviews or meta-analyses have simultaneously addressed the optimal choice of agent, the selection of patients who are infected and the timing of intervention.”
Since clindamycin is active against organisms associated with spontaneous preterm labor and preterm birth, the team conducted a meta-analysis of five randomized controlled trials of this antimicrobial in a total of 2346 women with abnormal genital tract flora, including bacterial vaginosis, at <22 weeks gestation.
The researchers found that 3.7% of women who received clindamycin delivered before 37 weeks of gestation, compared to 6.2% in the control group (pooled RR=0.60; p<0.001). Data from two studies indicated that clindamycin also reduced the risk of late miscarriage (RR=0.20).
The team calculated that 40 women would need to be treated (NNT) before 22 weeks of gestation with clindamycin rather than with placebo to prevent one case of spontaneous preterm birth.
The authors found that the evidence was strongest for oral clindamycin rather than clindamycin vaginal cream.
They conclude that the results are robust, and could justify “a further large multicenter randomized controlled trial of universal early screening and treatment of bacterial vaginosis with oral and/or clindamycin vaginal cream for the prevention of preterm birth which is sufficiently powered to assess neonatal and long term outcome.”