Q: Can medications be harmful during pregnancy?

A: Drugs are usually categorized into categories A, B, C, D, or X with regard to their effect on pregnancy. Most drugs on the market are category A or B, which means they are safe to take during pregnancy. Only a few are in Category X, which means they are "teratogens" (inducing fetal malformations or a miscarriage).  

When the effect on pregnancy of specific medications is being assessed, many possible issues are involved. These include questions such as when these drugs were taken during pregnancy, the amount taken, and the pregnant woman's history and background. Patients who take specific medications should talk to their doctor or a genetic counselor about their concerns. You should not stop a medication without first talking to your doctor, because the side effects of not taking them could be worse than continuing the medication.