In 2015, the US Food & Drug Administration (FDA) began overseeing the phase-out of pregnancy risk categories (A, B, C, D, and X) from prescription drug labeling and began requiring information from available human and animal studies of (1) known or potential maternal or fetal adverse reactions, and (2) dose adjustments needed during pregnancy and the postpartum period. Additional information is available at the FDA website:
Pregnancy and Lactation Labeling Final Rule.
Reproduced with permission from: Schatz M, Hoffman CP, Zeiger RS, et al. The course and management of asthma and allergic diseases during pregnancy. In: Allergy: Principles and Practice, Middleton E, Reed CE, Ellis EF, et al (Eds), St. Louis, Mosby, 1998. Copyright © 1998 Mosby.