Which category requires adequate, well-controlled studies in pregnant women showing no increased risk?

• A. Category D
• B. Category A
• C. Category C
• D. Category X

Answer: (B)

In deciding safety during pregnancy, the strongest evidence comes from human studies. The category that requires adequate, well-controlled studies in pregnant women showing no increased risk to the fetus is the one that signals proven safety in humans. This means there are high-quality clinical trials in pregnant women demonstrating no fetal harm.

Other categories reflect data from animal studies or less definitive human data, with varying levels of risk indicated. For example, one category includes drugs that have shown no risk in animals but lack adequate human studies, another flags potential risk in animals or uncertain human data, and the most restrictive categories identify known fetal harm or clear contraindication.