OBJECTIVE:To review the current Food and Drug Administration (FDA) pregnancy labeling system, examine the new FDA-proposed pregnancy labeling system for form and content, and provide comments on its suitability for implementation.DATA SOURCES:Data were obtained from the FDA's Web site (www.fda.gov), PubMed, Federal Register, LexisNexis, Physician's Desk Reference (PDR), Drugdex, and Current Contents.STUDY SELECTION:Research and articles involving drugs and pregnancy, drugs and lactation, and the subcommittee meeting of the FDA were included.DATA EXTRACTION:Prospective, case-control studies from pregnancy registries.DATA SYNTHESIS:Currently, only 40% of drugs in the PDR have pregnancy categories listed. The medical profession has resorted to other means to assess pregnancy risk, such as retrospective chart review, case reports, and consultation with experts such as regional drug information centers.CONCLUSIONS:The proposed pregnancy labeling system strives for more clinical usefulness by reliance on human data derived from pregnancy registries. The clinical usefulness of the new labeling remains to be seen.