Breast Cancer Home > Femara and Pregnancy
Femara is not meant for use in pregnant women. The FDA has given Femara a pregnancy Category X classification, meaning that the drug has shown clear evidence of risk to the fetus in previous studies. You should be sure to let your healthcare provider know (prior to taking Femara) if you are pregnant or thinking of becoming pregnant.
An Overview of Femara and PregnancyFemara® (letrozole) is generally not considered safe for women who are pregnant. In previous animal studies involving Femara and pregnancy, the drug caused miscarriages and birth defects.
What Is Pregnancy Category X?
The U.S. Food and Drug Administration (FDA) uses a category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category X is given to medicines that have shown clear evidence of risk to the fetus in studies. With this category, the potential risks clearly outweigh the potential benefits.
Femara was given a pregnancy Category X rating because of problems it caused in animal studies. When given to pregnant rats and rabbits, the drug increased the risk of miscarriages and birth defects (including kidney or urinary tract problems and bone problems).
It is important to remember that Femara is approved for use only in postmenopausal women and has not been shown to be effective in premenopausal women, including pregnant women.
Although Femara is not safe for use during pregnancy, it is sometimes used in an "off-label" fashion before pregnancy to help women get pregnant (see Clomid vs. Femara).