Revamped drug labels will give pregnant and breastfeeding women more information on a medication’s risks.

Taking medication during pregnancy or breastfeeding is tricky for many women. They may not know whether a given medication is safe for them and their baby or if they need to adjust their dose.

But things just got a little easier. The U.S. Food and Drug Administration (FDA) said Wednesday it is revamping labels on prescription drugs. The new labeling system will make it easier to tell which medications are safe for infants and developing fetuses.

Six million women get pregnant in the United States every year. The typical American woman takes an average of three to five prescription drugs during a pregnancy, according to the FDA. They take medication for asthma, high blood pressure, and other ongoing medical conditions. Some take prescription drugs for health problems that get worse during pregnancy, or for new conditions that develop. Since a pregnant woman’s body changes during nine months of gestation, she may need to adjust medication doses, too.

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Drugs are currently labeled using one of five letters — A, B, C, D, and X. These letters indicate the overall risk of using a medication during pregnancy and breastfeeding. But even the FDA admits this lettered scale can be confusing.

“The letter category system was overly simplistic and was misinterpreted as a grading system, which gave an over-simplified view of the product risk,” said Dr. Sandra Kweder, deputy director of the Office of New Drugs in the FDA’s Center for Drug Evaluation and Research, in an agency press release. 

Dr. Joanne Stone, director of maternal and fetal medicine at The Mount Sinai Hospital in New York City, told Healthline, “These categories are often not helpful in providing detailed information relevant to making decisions about use in pregnancy and lactation.”

The new system aims to organize the information more clearly and consistently. Starting June 30, new drug labels will have categories for “Pregnancy,” “Lactation,” and “Females and Males of Reproductive Potential.” “Pregnancy” will include information on medication use during pregnancy, labor, and delivery. The “Lactation” category will offer information on whether a medicine gets into breast milk and how it may affect an infant. The “Females and Males of Reproductive Potential” category will discuss birth control, prenatal tests, and a medicine’s impact on fertility.

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“This is a much needed change and will provide patients and healthcare providers with specific and relevant information, including data from drug trials and registries,” Stone said.

Labels for older drugs will be phased in within three to five years.

The new labeling rules only apply to prescription medications, not over-the-counter drugs. Pill bottles aren’t required to contain the information. Instead, the revamped information will be in the documents patients are usually given along with medications at the pharmacy and that doctors receive from drug companies.

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