When physicians and nurses see patients, they must be able to understand and discuss how drugs are labeled with regard to pregnancy and lactation. This article describes the current and proposed U.S. Food and Drug Administration (FDA) classification system for pregnancy and lactation labeling. Using data from animal and human studies, the FDA currently classifies drug safety into five categories; however, there is no current standard FDA classification system to categorize risk for lactation. Because the current labeling category system has been criticized, the FDA has proposed a revision of the system. The proposed change to the labeling system would provide more detailed, comprehensible, and practical information about the use and effects of drugs during pregnancy and lactation.