Use of popular antifungal drug during pregnancy doubles risk of miscarriage
Use of a popular oral antifungal drug during pregnancy doubles risk of miscarriage.Pregnant women who take commonly used medication fluconazole to treat vaginal yeast infections may be more likely to have miscarriages than women who don’t take this pill during pregnancy, a Canadian study suggests. The new research has been published in CMAJ (Canadian Medical Association Journal).
One in 10 pregnant women develop yeast infections, a risk that is up to 10 times higher than in nonpregnant women, researchers note in CMAJ.While topical treatments are the first line for pregnant women with fungal infections, oral fluconazole is often used during pregnancy.
“Regardless of dosage, oral fluconazole use is associated with the risk of spontaneous abortions,” said lead study author Anick Bérard of the University of Montreal in Quebec.
Researchers looked at data on 441 949 pregnancies from the Quebec Pregnancy Cohort between 1998 and 2015, linking to filled prescriptions listed in the Quebec Prescription Drug Insurance database.For the current study, they examined data on 29,458 pregnancies ending in miscarriage between 6 and 19 weeks gestation and on 245,059 pregnancies that didn’t end in miscarriage.
Women who took low doses of fluconazole (150 milligrams) were more than twice as likely to have a miscarriage as women who didn’t use this drug at all during pregnancy, and women who took higher doses of the drug had more than triple the miscarriage risk.
"Our study shows that taking any dose of oral fluconazole while pregnant may be associated with a higher chance of miscarriage," says Dr. Anick Bérard, Université de Montréal, Montréal, Quebec. "Taking higher doses of fluconazole over 150 mg in early pregnancy may be linked to a higher chance of a newborn with a heart defect."
The study is consistent with other studies, although more research is needed as the study sizes are still small.
“The recommended treatment of choice in pregnancy for vaginal yeast infections are topical antifungal agents (clotrimazole, miconazole) that are administered via the vagina in the form of cream or vaginal tablet,” Paquette said by email. “These agents have been shown to be safe and effective in pregnant women.”
Even though oral fluconazole is available on drugstore shelves without a prescription, “oral fluconazole treatment for vaginal yeast infections in pregnant women should be avoided at this time,” Paquette added.
In a related commentary, Drs. Vanessa Paquette and Chelsea Elwood, British Columbia Women's Hospital and Health Centre, Vancouver, BC, write, "The study re-emphasizes safe prescribing practices in pregnancy, which include confirming the correct diagnosis and then choosing the safest medication with the largest body of data in pregnancy at the lowest appropriate doses."