Osphena and Pregnancy
When given to pregnant animals, Osphena (ospemifene) caused a number of problems, such as miscarriages and prolonged and difficult pregnancy and labor. Because this drug is only approved for use in women who have gone through menopause, there is no reason for a pregnant woman to use Osphena. Research has shown that the risks to the fetus clearly outweigh any benefits of the drug.
Osphena™ (ospemifene) is a prescription medication used to treat dyspareunia (painful intercourse) in postmenopausal women. Based on animal studies, this medicine may be harmful if taken during pregnancy. It should not be used by women who are or may become pregnant.
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. Osphena is classified as a pregnancy Category X medication.
Pregnancy Category X is given to medicines that show problems to the fetus in animal studies or in human use of the medication. With this category, the potential risks clearly outweigh the potential benefits.
In animal studies, Osphena increased the risk for miscarriage when given to pregnant rabbits and rats. It also caused prolonged and difficult pregnancy and labor in the pregnant rats.
Osphena is a selective estrogen receptor modulator, which means it works like estrogen in some areas of the body, such as the lining of the uterus, but may work like an anti-estrogen in other areas of the body. The effects observed when Osphena was given to pregnant rats and rabbits are likely related to the drug's actions on estrogen receptors. Because disruption of estrogen can cause problems during pregnancy, it would be expected that Osphena would also cause problems during pregnancy.
It is important to keep in mind that this medicine is not approved for use in premenopausal women. Therefore, it should not be taken by women who are pregnant or who may become pregnant.