CLINICAL QUESTION

Does treatment of bacterial vaginosis in male partners reduce the likelihood of bacterial vaginosis recurrence in women?

BOTTOM LINE

In addition to the treatment of bacterial vaginosis in women, treating it in their male partners with oral and topical metronidazole decreased the likelihood of bacterial vaginosis recurrence in women (number needed to treat [NNT] = 3). Getting men to adhere to the regimen is key. (Level of Evidence = 1b−)

SYNOPSIS

Recurrence of bacterial vaginosis after treatment is common in women and is thought to be related to reexposure to bacterial species associated with bacterial vaginosis that are harbored by men. Previous studies of treating male partners with oral metronidazole had mixed results. The researchers identified 164 women 18 years and older with a regular male partner for at least 8 weeks. The women had a diagnosis of bacterial vaginosis based on having three or more Amsel criteria (vaginal pH > 4.5, fishy odor, clue cells on microscopy, and a homogeneous vaginal discharge) and a microscopic Nugent score of at least 4 out of 10. Of the original 164 women, 27 were lost to follow-up. They were treated with oral metronidazole, 400 mg twice daily or, if contraindicated, intravaginal 2% clindamycin for 7 nights or 0.75% metronidazole gel for 5 nights. The women were asked to refer their partners who were then enrolled in the study if they presented within 1 week. The male partners in the treatment group received oral metronidazole, 400 mg twice daily for 7 days and 2% clindamycin cream to be applied twice daily to the glans penis and upper shaft of the penis (and under the foreskin, if present). At baseline, the average age of the female participants was 29 years, the average age of the male participants was 32 years, 80% of the men were not circumcised, and the women had a median of three previous diagnoses of bacterial vaginosis. Groups were balanced, and the primary analysis was for the modified intention-to-treat population who took at least one dose of medication and had assessment for recurrence. At 12 weeks, recurrence had occurred significantly less often in the partner treatment group than in the control group (35% vs 63%; P < .05; NNT = 3.5). Results were similar for the full intention-to-treat population (n = 159) and the per-protocol population (n = 134). Only 47 of 80 men were at least 70% adherent to the protocol. The number of days to recurrence was significantly longer in the partner treatment group than in the control group. Adverse events were what was expected after 1 week of taking metronidazole; only four men in the treatment group reported any redness or irritation of penile skin.