There is evidence that bacterial vaginosis is associated with an increased incidence of adverse pregnancy outcomes (e.g., premature rupture of membranes, pre-term delivery and low birth weight). Symptomatic pregnant women should be treated, and those with a history of previous pre-term delivery should be screened to detect asymptomatic infections. Pregnant women with recurrence of symptoms should be re-treated. Screening of asymptomatic pregnant women without a history of prior pre-term delivery is not recommended.

Metronidazole is not recommended for use in the first trimester of pregnancy, but it may be used during the second and third trimesters. Lower doses of metronidazole are recommended throughout pregnancy, to reduce the risks of any adverse effects.

Recommended regimen

• metronidazole, 200 or 250mg orally three times daily for 7 days.

Alternative regimens

• metronidazole, 2g orally, as a single dose

OR

• clindamycin, 300 mg orally twice daily for 7 days

OR

• metronidazole gel, 0.75%, 5g twice daily intravaginally for 7 days.