Safety Rating Systems for Drugs Used in Pregnancy and Lactation

The most widely used systems for categorizing drug risk during pregnancy in the United States are the Food and Drug Administration (FDA) and Teratogen Information System (TERIS) pregnancy risk classifications. Controlled data on using medications during pregnancy and lactation are lacking, making firm recommendations more difficult. Only fair agreement on risk category assignment exists when comparing common pregnancy risk classification systems within and between countries. Pregnancy risk categories should be used as general guidelines to help choose safer medication alternatives. Useful print and Internet resources help guide rational medication selections during pregnancy and lactation.