This sheet talks about exposure to fluconazole in pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your healthcare provider.

What is fluconazole?

Fluconazole is a medication used to treat yeast and fungal infections. A single dose of 150 mg is the most commonly used dose to treat vaginal yeast infections. For fungal infections, daily doses of up to 800 mg daily have been used. Fluconazole is sold under the brand name Diflucan®.

I take fluconazole. Can it make it harder for me to get pregnant?

An experimental animal study did not find fluconazole to affect fertility. Studies in women have not been done to see if fluconazole could make it harder for to get pregnant.

I just found out I am pregnant. Should I stop taking fluconazole?

Talk with your healthcare providers before making changes to this medication. Discuss what treatments are best for you.

Does taking fluconazole increase the chance for miscarriage?

Miscarriage can occur in any pregnancy. Studies looking at the use of low doses of fluconazole did not find a higher chance of miscarriage in two studies that involved over 500 women who used fluconazole in the months before or during their pregnancy. One study among almost 600 women suggested an increased chance for miscarriage if a mother used any dose of fluconazole during early pregnancy. Another study looked at miscarriages among women who filled a prescription for single-dose oral fluconazole for vaginal yeast infection between weeks 7 and 22 weeks of their pregnancy. They found a slightly higher chance of miscarriage than expected. This prescription-type of study cannot tell if these women actually used the medication after filling their prescription, and has other flaws; making it hard to confirm that the chance for pregnancy loss was really higher in this group.

The FDA issued a statement in October 2019 that indicated available studies do not provide definite evidence of an increased chance for miscarriage with a single 150 mg dose of oral fluconazole.

Does taking fluconazole during the first trimester of pregnancy increase the chance of birth defects?

In every pregnancy, a woman starts out with a 3-5% chance of having a baby with a birth defect. This is called her background risk.

When looking at fluconazole use in pregnancy, the answer to this question may depend on the dose and the length of time the medication is used. Most data suggests that the use of low doses of fluconazole (mostly a single dose of 150 mg) during the first trimester of pregnancy did not show an increased chance of birth defects. Another study with 7,000 women who used lower doses of fluconazole (150 to 300 mg) did not show an increased chance for birth defects after first trimester use. The information on higher dose exposure is unclear. One study has reported that exposure to a dose higher than 150 mg in the first trimester might increase the chance for a heart defect called septal defects. (The septum is the wall in heart that divides it in two halves). A pattern of birth defects of the head, face, bones and heart were reported in the five children of four mothers that took high doses (400 to 1200 mg per day) of fluconazole for many weeks to treat severe fungal infections. These cases on their own cannot prove cause and effect, but the unusual infant findings have raised concern that the high dose of fluconazole may be the cause of the birth defects.

In summary, it is unlikely that the use of a single low dose of fluconazole during early pregnancy would greatly increase the chance of birth defects. However, the use of high dose fluconazole for many weeks might be associated with a small increase of birth defects.

Could taking fluconazole in the second or third trimester cause other pregnancy complications?

Studies have not found an increase in premature birth (birth before 37 weeks of pregnancy) or low birth weight following a single dose of fluconazole. One study did not find an increased chance for stillbirth with any use of fluconazole.

Does taking fluconazole in pregnancy cause long-term problems in behavior or learning for the baby?

Studies have not been done to see if fluconazole use in pregnancy would cause learning or behavior issues.

Can I breastfeed while taking fluconazole?

While it hasn’t been well studied during breastfeeding, fluconazole is commonly prescribed during this time. Fluconazole can enter breast milk, but the dose to the breastfed infant would be much less than the dose used to treat an infant with an infection. The treatment of a vaginal infection often requires only a single dose of fluconazole and is unlikely to pose a risk to the breastfed infant.

If you have a yeast infection of your breast, your infant might also have oral thrush (a yeast infection in the mouth). In your child does have an infection, they will also need medical treatment, because the amount of fluconazole transferred through breast milk is not enough to treat the nursing child.

Talk with your healthcare provider about all your breastfeeding questions.

If a man takes fluconazole, could it affect his fertility (ability to get partner pregnant) or increase the chance of birth defects? 

There is one animal study that found lowered sperm count while the animal was exposed to fluconazole. Sperm counts returned to normal two months after stopping treatment. There is no evidence to suggest that a father’s use of fluconazole increases the chance for birth defects. In general, exposures that fathers have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet on Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/pdf/

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