Pregnant women are more susceptible to yeast infections due to hormone changes, specifically estrogen levels that are thought to affect the normal pH balance in the vagina.

A recent study from Denmark has found a link between use of the oral yeast medication fluconazole (brand name Diflucan) used to treat yeast infections and increased risk of miscarriage.

In response, the FDA has released a April 2016 safety alert cautioning women about taking Diflucan or health providers prescribing it until the FDA has had more time to review the study findings.

The current FDA label suggested that a single dose of 150 mg of oral fluconazole does not show increased risks, but birth abnormalities have been reported when women took high doses (400-800mg).

“In the Danish study, most of the oral fluconazole use appeared to be one or two doses of 150 mg,” noted the alert.

Researchers from the Department of Epidemiology at the University of Copenhagen reviewed the records of over 1.4 million pregnancies over a 17-year span of time.

“Among 3315 women exposed to oral fluconazole from 7 through 22 weeks’ gestation, 147 experienced a spontaneous abortion, compared with 563 among 13 246 unexposed matched women,” the study reported. “There was a significantly increased risk of spontaneous abortion associated with fluconazole exposure.”

The study also compared women who took oral fluconazole against azoles (topical yeast infection medications). Out of almost 3,000 women, 130 who took oral fluconazole had spontaneous abortions versus 118 of those treated with topical azoles.

The CDC recommends that pregnant women only use topical azole therapies applied for seven days for the treatment of vulvovaginal candidiasis.

It is estimated that approximately 10 percent of pregnant women develop yeast infections, according to the Danish study.

The New York Times contacted Rachel Hooper, a spokeswoman for Pfizer, the maker of fluconazole. An email in response from Pfizer stated that the drug “has a well-established benefit risk profile supported by more than 25 years of patient experience.”

However, in view of the recent Danish study, “Patients who are pregnant or actively trying to get pregnant should talk to their health care professionals about alternative treatment options for yeast infections,” recommends the FDA.

Michele is an R.N. freelance writer with a special interest in woman’s healthcare and quality of care issues.

Edited by Jody Smith