Skip to Main Content

Federal health officials on Wednesday rolled out two new draft guidances about how to study drug safety and efficacy in pregnant and lactating women, the latest in a series of steps to make sure women have the information they need to make medical decisions.

The draft documents, released by the Food and Drug Administration, give drug makers insight into the agency’s thinking on when they should study a medicine in lactating women and how they can better monitor outcomes in pregnant women who are taking medications that have already been approved. The documents fall in line with 2018 recommendations made by a federal task force formed by Congress to study the lack of research involving pregnant and lactating women.


“Often, women and their health care professionals must make decisions about whether to use a drug during pregnancy or lactation even when relevant safety data are scant or lacking,” Dr. Amy Abernethy, principal deputy commissioner of the FDA, and Dr. Janet Woodcock, director of the FDA’s Center for Drug Evaluation and Research, said in a statement.

For decades, the drug industry has steered clear of research involving pregnant women out of the concern that an experimental medication might harm a fetus. There’s a similarly small amount of research on medication safety in lactating women. That’s left patients and their health care providers guessing about whether many medicines are safe to take, are being delivered at the right dose, or will affect their milk production.

Health officials are increasingly encouraging drug makers to help address that information gap. Last spring, the FDA issued draft guidance for drug makers that outlined how to safely and ethically include pregnant women in clinical trials. The two new draft documents give drug makers even more direction about how to gather more useful data.


“The draft guidances are an additional step the agency is taking toward getting women who are pregnant or breastfeeding important safety information about their medications, so they can make informed decisions about their health and the health of their babies,” Abernethy and Woodcock said.

The FDA already requires some drug makers to run studies on how a medication works in lactating women and whether it’s transferred to breast milk. In its new draft guidance, the FDA outlines situations in which drug makers might want to conduct a lactation study, even when it’s not required. The FDA points to several examples: when an experimental drug is likely to be used by reproductive age, when a drug maker is seeking approval for a new indication of an existing medicine and it’s likely to be used by lactating women, and when existing medications are commonly being used by women of reproductive age.

The agency also addresses some of the ethical questions around including lactating women in research, such as when lactating women participating in research should stop breastfeeding or discard their milk.

The second draft guidance outlines how to design new studies and leverage existing data to more closely monitor outcomes in pregnant women who are taking approved medicines. Some drug companies currently use pregnancy registries — in which women taking a medication while pregnant sign up to share their data — to collect data on adverse events such as birth defects. But enrolling women and retaining them as participants in the registries is difficult. In its draft guidance, the FDA says that there are other ways to collect more data, including electronic health records and insurance claims.

The FDA said that once they’re finalized, the documents will help companies collect more high-quality safety information about drugs used in pregnant and lactating women. The draft guidances are open for public comment until early July.