A new study examining the effect prescription drugs have on pregnant women is to be funded by the US Food and Drug Administration (FDA).
The agency announced at the end of last month that it is to set up a new research program entitled the Medication Exposure in Pregnancy Risk Evaluation Program (MEPREP).
Few clinical trials have tested the safety of drugs in pregnancy due to fears for the health of women and their unborn children.
However, according to an article published in the American Journal of Obstetrics and Gynecology, almost two-thirds of American women have taken at least one prescription drug during their pregnancy.
Dr Gerald Dal Pan, director of the Office of Surveillance and Epidemiology at the FDA's Center for Drug Evaluation and Research, said: "Results of these studies will provide valuable information for patients and physicians when making decisions about medication during pregnancy."
The research is to be conducted in collaboration with care organisation Kaiser Permanente, Vanderbilt University and the HMO Research Network Center for Education and Research in Therapeutics (CERT).