Disclaimer: The medical information published on this page is not intended to serve as a substitution for a thorough evaluation from a qualified healthcare provider. Please contact your midwife if you have questions about illness or medication safety. 

In the United States, medication is assigned a pregnancy category based on evidence of teratogenic (causing developmental malformations) effects to the developing fetus. Below is a list of common medications, their pregnancy categories and if they are considered safe to take in each trimester. Please contact your midwife if you have questions about illness or specific medication questions.

FDA Classification of Drug Safety During Pregnancy

Category A

Controlled studies in women fail to demonstrate a risk to the fetus in the first trimester (and there is no evidence of risk in later trimesters), and the possibility of fetal harm appears remote.

Category B

Either animal reproduction studies have not demonstrated a fetal risk but there are no controlled studies in pregnant women, or animal reproduction studies have shown an adverse effect (other than a decrease in fertility) that was not confirmed in controlled studies in women in the first trimester (and there is no evidence of risk in later trimesters).

Category C

Either studies in animals have revealed adverse effects on the fetus (teratogenic or embryocidal or other) and there are no controlled studies in women, or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the fetus.

Category D

There is positive evidence of human fetal risk, but the benefits from use in pregnant women may be acceptable despite the risk (e.g., if the drug is needed in a life-threatening situation or for a serious disease in which safer drugs cannot be used or are ineffective).

Category X

Studies in animals or human beings have demonstrated fetal abnormalities or there is evidence of fetal risk based on human experience, and the risk of the use of the drug in pregnant women clearly outweighs any possible benefit. The drug is contraindicated in women who are or may become pregnant.

Category N

The FDA has not classified the drug.