Fluconazole and Risk for Adverse Pregnancy Outcomes

Fluconazole is most commonly prescribed for vaginal yeast infections, which can be resolved with a single 150-mg dose. Higher doses are indicated for systemic fungal infections. To evaluate the safety of fluconazole during pregnancy, Canadian investigators conducted a nested case-control study in a cohort of 440,000 pregnant women who delivered in Quebec from 1998 through 2015. Fluconazole dosages were stratified into low (≤150 mg) or high (>150 mg).

Overall, <1% of women received fluconazole during pregnancy; of these, 70% received a single low dose. Compared with no fluconazole exposure, low-dose and high-dose exposure were associated with excess risk for spontaneous abortion (adjusted odds ratios, 2.2 and 3.2, respectively). High-dose flu…