Propecia and Pregnancy

Is Propecia Safe During Pregnancy?

For women who are pregnant, PropeciaŽ (finasteride) is very dangerous. This is based on animal studies that looked at the effects of Propecia during pregnancy. Propecia has been given a pregnancy Category X classification based on its risks to the unborn fetus.

Propecia and Pregnancy Category X

The U.S. Food and Drug Administration (FDA) uses a pregnancy 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 show problems to the fetus in animal studies or in humans who have mistakenly taken the medicine. The use of a pregnancy Category X medicine during pregnancy is not recommended.

Propecia should not be used in women who are pregnant or may become pregnant. In fact, women who are or may be pregnant should not touch broken or crushed Propecia tablets.

Propecia, Pregnancy, and Birth Defects

Propecia works by blocking the conversion of testosterone into DHT (dihydrotestosterone), thereby decreasing the amount of DHT in the body. Since DHT is important for male genital development, if it taken during pregnancy, Propecia may cause abnormalities to the external genitals of a male fetus.

Can Propecia Be Used by My Partner While I Am Pregnant?

It appears that when Propecia is used by the male partner during pregnancy, no problems with the fetus will occur. This is based on data that looked at doses up to 250 times the amount of Propecia found in semen. These studies were conducted with monkeys, a species that closely resembles humans when looking at fetal development. As discussed above, however, if your partner is using Propecia, it is extremely important that you do not touch any broken or crushed Propecia tablets. Unbroken tablets are safe to touch because they have a protective coating.

PROPECIA is not indicated for use in women.

Administration of finasteride to pregnant rats on gestational days 6-20 at doses ranging from 100 mg/kg/day to 100 mg/kg/day (1-684 times the human exposure, estimated) resulted in dose-dependent development of hypospadias in 3.6 to 100% of male offspring. Pregnant rats produced male offspring with decreased prostatic and seminal vesicular weights, delayed preputial separation, and transient nipple development when given finasteride at ≥30 µ g/kg/day (0.2 times the human exposure, estimated) and decreased anogenital distance when given finasteride at ≥3 µg/kg/day (0.02 times the human exposure, estimated). The critical period during which these effects can be induced in male rats has been defined to be days 16-17 of gestation. The changes described above are expected pharmacological effects of drugs belonging to the class of Type II 5a-reductase inhibitors and are similar to those reported in male infants with a genetic deficiency of Type II 5a-reductase. No abnormalities were observed in female offspring exposed to any dose of finasteride in utero.