Treating the male partner of women with bacterial vaginosis (BV) with both oral and topical antibiotics can significantly reduce recurrence, an Australian study published in the New England Journal of Medicine last week has found.

Sixty-three percent of women who were receiving standard care had a recurrence within 12 weeks – compared with 35% of the women whose partners were treated as well.

The open-label randomised controlled trial included 164 heterosexual, monogamous couples – with 87% of the women having a history of BV.

Women in the control group received first line treatment, but their partner was not treated, while men in the partner-treatment group received metronidazole 400-mg tablets and 2% clindamycin cream applied to penile skin, both twice daily for seven days.

At the interim analysis it was clear that the intervention was superior to standard care – so the trial was stopped early when 150 couples reached the 12-week follow up.

Does this study have real world implications right now?

Yes, says Dr Sara Whitburn, medical director at Sexual Health Victoria, noting that Melbourne Sexual Health Centre has already updated its treatment guidelines.

“If you have someone who is in a monogamous heterosexual relationship, I do think this study actually could be put in place and change management now,” she says, noting that the decreased recurrence of BV in the intervention group was significant enough to stop the study early.

Half of women who get BV experience recurrence within 12 months, impacting their quality of life, sex life and health.

“We know that 50% of people who get BV are going to have a relapse. So it’s quite a high proportion of people,” Dr Whitburn says. “So I think it shows that in this group, it’s certainly something to consider.”

Preliminary trial data was compelling enough that Dr Whitburn was already offering male partner treatment in cases where women had tried multiple other options without success.

“Now with the full randomised controlled trial, and also the updating of the guidance from Melbourne Sexual Health, I will be offering it for this population as an option when managing someone with a recurrence,” Dr Whitburn says.

Dr Yasmin Tan, a gynaecologist at Royal Women’s Hospital in Randwick agrees that treating the male partner makes sense for people with recurrent BV episodes, “as long as there’s no risk to the partner, they’re not allergic to the antibiotic or got gut issues or some other contraindication.”

However, it’s important to note that the trial only included monogamous couples.

“We still don’t know how effective it is for someone that might have more than one partner,” Dr Whitman says.

Risk factors for recurrence

The study population “had a high burden of risk factors for recurrence”: 87% had a history of BV, 80% had an uncircumcised partner, and nearly a third had an IUD.

“There has been some research in the past that for somebody with a copper IUD, that there was a higher prevalence of bacterial vaginosis,” Dr Whitburn explains. “We still are looking for more research into hormonal IUDs.”

“However, if someone is having recurrence in bacterial vaginosis, after a discussion of their contraceptive and their menstrual needs, offering to remove the IUD might be part of your management plan if other options haven’t helped,” she says.

The trial wasn’t powered to differentiate the association between IUDs, having an uncircumcised partner and recurrence — but Dr Tan says she would consider these risk factors, as well as whether the woman was pregnant, in her decision-making.

“I think if the man was uncircumcised and the woman had an IUD or she was pregnant, I’d definitely have a lower threshold to treat the partner,” Dr Tan says.

Adverse events and adherence

In the study, 46% of males who received treatment had any side effect, such as nausea (14%), headache (12%), metallic taste (7%) or irritation of the penile skin (7%).

There were no serious adverse events, and adherence was quite high – 14% of male participants took less than 70% of the prescribed medicines.

(By contrast, around 58% of women in the study experienced side effects, and no females reported taking less than 70% of the medicines.)

“I think the issues are, in real life, male compliance with treatment may not be so high. But there didn’t seem to be a lot of adverse effects or risk from taking the antibiotics from the male,” Dr Tan notes. “They might get some irritation from the cream or they might get a little bit of GI upset, but overall, there wasn’t a reason not to treat the men.”

What about same sex partners?

For women in same-sex relationships, it is currently recommended to treat both partners. “That’s at the evidence level of a clinical recommendation,” she adds, but the researchers have begun another study in the LGBTQI community to strengthen the evidence.

“There’s a high concordance of if somebody in a same-sex relationship tests positive for BV and has symptoms, their partner is likely to also test positive for BV,” Dr Whitman explains.

Patient education

The study authors, who are from Melbourne Sexual Health Centre, have developed several resources to support health professionals with BV partner treatment.

“One of the things to consider is that they use the clindamycin vaginal gel as the treatment for the person with the penis,” Dr Whitburn says.

To avoid confusion, she recommends educating patients around what it might say on the prescription.

“It’s about supporting our pharmacy colleagues to know that we might be prescribing a vaginal gel for someone with a penis,” she adds.

She suggests doctors familiarise themselves with the study and the Melbourne Sexual Health Centre information for health professionals, to help them feel confident about how to prescribe and what patient education to give.

More information:

Bacterial vaginosis treatment guidelines – Melbourne Sexual Health Centre (MSHC)

BV information for health professionals – Melbourne Sexual Health Centre (MSHC)

Male-Partner Treatment to Prevent Recurrence of Bacterial Vaginosis | New England Journal of Medicine