Science & Research

Pregnancy Research Initiatives

Pregnancy Research Initiatives: Enhancing Health for Mother and Child

Many pregnant women need to take medicine.

In the United States (U.S.), there are 60 million women of reproductive age. Over 9 million of these women have chronic asthma, hypertension or epilepsy and require ongoing or episodic treatment with prescription medication. Approximately 10% of women between the ages of 15 and 44 become pregnant annually. Thus, many women who become pregnant require medication. Also, new medical problems may develop or old ones may become more severe during pregnancy. These medical problems often require treatment with prescription medication.

Many babies are exposed to medicine unintentionally.

About half of all pregnancies in the U.S. are unintended. For prescription medicines used in women of childbearing age, it is common for medication exposure to occur during the critical period of fetal development, before the woman is aware of her pregnancy.

The FDA supports initiatives that address the use of FDA-regulated products during pregnancy.

  • Information on fetal safety - During clinical development of most medicines, pregnant women are actively excluded from trials, and, if pregnancy does occur during the trial, the usual procedure is to discontinue treatment and drop the woman from the study. Consequently, at the time of a medicine’s initial marketing, except for products developed to treat conditions unique to pregnancy, there are seldom meaningful human data on the effects of that medicine during pregnancy. Even after years of marketing, information on fetal safety of medicine in human pregnancy is usually not available. To address this problem, the Food and Drug Administration (FDA) has issued guidance on how to conduct a pregnancy exposure registry for the collection of fetal safety data.
  • Promoting healthy pregnancies - Under FDA’s Pregnancy Labeling Initiative, the Agency is taking a two-pronged approach for improving fetal safety and maternal dosing information. First, the FDA is drafting new regulations on the format and content of the pregnancy and lactation section of the label for prescription medicines. Second, the agency is working to improve the quality and quantity of information that is available to be put into the label.
  • Helping practitioners prescribe for pregnant women - The new proposed label will provide clinically relevant information useful for 1) treating women during pregnancy and lactation, and 2) counseling pregnant or lactating women regarding the effects of medicine on herself, her developing baby, or her breastfed child. The revised regulations will significantly improve the way the agency communicates risk information and provide for efficient risk management during pregnancy.
  • Information on dosing - When deciding on the right dose of medicine for a pregnant woman, healthcare practitioners usually rely on information from studies on non-pregnant individuals. Since pregnancy influences the action of many medicines, these practices risk exposing the fetus to medicine with little or no benefit to the mother. Knowledge about correct dosing in pregnant women can only be obtained by studying the activity of the medicine throughout the pregnancy.
  • Research on medications used in pregnancy - OWH has funded research on two prescription medicines commonly used to treat high blood pressure during pregnancy. The studies will determine the dose of medicine that provides the greatest benefit and least risk for the mother and her baby. The studies, which are being conducted at two National Centers of Excellence in Women’s Health, will demonstrate that this type of study can and should be done for medicines widely used during pregnancy. Research in this area will continue with studies to determine if dosing adjustments are needed for antidepressants used during pregnancy.
  • Counter-terrorism activities - As part of FDA’s counter-terrorism activities, the FDA Office of Women’s Health and Center for Drug Evaluation and Research have funded studies on prescription medicine that may be used to treat conditions that could occur after a terrorist attack in special populations; pregnant and lactating women and the elderly. One type of study will determine the appropriate dose of medicines used in these populations. The other study type will evaluate the fetal outcomes of pregnant women exposed to these medicines using a Medicaid claims database.
  • Pregnancy Resgistry Web Portal - A Pregnancy Registry is the most effective technique for collecting information on the fetal safety for prescription medicines. In May 2002, the FDA Office of Women’s Health launched a new website listing registries in the United States and Canada that are currently enrolling pregnant women. The website helps women learn more about pregnancy registries and how to participate in them. The website also provides links to other sources of information regarding the fetal safety of medicines used during pregnancy. For more information, visit

Contact FDA

Food and Drug Administration Office of Women's Health

10903 New Hampshire Avenue


Silver Spring, MD 20993

Page Last Updated: 12/18/2014
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