UW News

October 30, 2001

University of Washington to study use of medications by pregnant women

The University of Washington National Center of Excellence in Women’s Health is conducting new research into how drugs are handled in the body by pregnant women, a field which according to the U.S. Food and Drug Administration (FDA) deserves more attention. The FDA is providing $150,000 for the research to identify the doses that will provide the greatest benefit and the least risk for the mother and her baby. Dr. Mary Hebert, associate professor in the UW Department of Pharmacy, Dr. Tom Easterling, associate professor of obstetrics and gynecology, and Dr. Gail Anderson, associate professor in pharmacy and pharmaceuticals, will be conducting the study evaluating a high blood pressure medication commonly prescribed for pregnant women.

“Very little work has been done on studying drugs in pregnancy, despite the fact that on the average, a woman will take about three drugs during her pregnancy, aside from those administered during birth,” Hebert, associate professor in the UW School of Pharmacy, said. “There is very little information known about how the body handles those drugs eliminated by the kidneys or metabolized by the liver over the course of a pregnancy. That’s what this study will focus on.”

An FDA study conducted in 1994 found this average number of prescriptions during pregnancy excludes prenatal vitamins, iron preparations and medications at the time of delivery. That number increased with age. Pregnant women over the age of 35 were taking an average of five prescriptions. The current study will help establish guidelines that will facilitate industry investigation of the drugs used commonly during pregnancy.

“Many drugs are absolutely necessary during pregnancy, particularly in women who have pre-existing conditions like high blood pressure or diabetes,” Hebert said. “As health-care providers, we are trained that the first goal during pregnancy is to avoid medications altogether. The reality is that illnesses need to be treated during pregnancy, whether they pre-exist or develop during the pregnancy.”

Hebert points out that kidney function changes dramatically during pregnancy, but there just isn’t enough data on hand currently to define how much this affects drug concentrations. A similar question exists for drugs that are metabolized by the liver.

“There are also changes in how the body responds to medication during pregnancy,” Hebert said. “The body may become less or more sensitive to a drug’s effect. There are a number of issues that need to be examined so we have enough information to prescribe medications intelligently during pregnancy.”

A similar award was made to the University of Illinois at Chicago. Both study centers are members of the Department of Health and Human Services National Centers of Excellence in Women’s Health. The U.S. Public Health Service’s Office of Women’s Health established these centers in the UW Schools of Nursing and Medicine in 1996 as models of health care for women.