Drugs: The Nine-Month Dilemma

Experts debate which prescription drugs are safe for pregnant women and developing fetuses.

By Carlin Flora, published November 1, 2004 - last reviewed on June 9, 2016

Nothing chills a pregnant woman's heart like tales of the drug thalidomide, which left thousands of infants with deformed limbs in the 1960s. But while thalidomide is now known to be teratogenic, the decision to take a drug while pregnant is often based on a subjective calculus that weighs the benefits of a pill against its potential risks to a developing fetus.

Indeed, when it comes to the safety of drugs, pregnant women and their doctors have little solid information. Government restrictions on the drug approval process are responsible for the dearth of data on how medications affect pregnant and breast-feeding women, says Kathleen Uhl, medical team leader for the Food and Drug Administration's new Pregnancy Labeling Team, charged with advising the public.

Most drugs are tested only on animal fetuses, leaving questions about human fetal safety and proper dosages largely unanswered. Uhl speculates that women and their doctors err on the side of over-cautiousness. "Our culture is petrified that any drug can cause a thalidomide baby," she says. "But very few drugs are known to cause birth defects."

Research has shown that pregnant women who take Prozac and other serotonin reuptake inhibitors do not have a higher risk of miscarriage or fetal abnormalities, although they do seem to be at a higher risk of premature birth. Untreated maternal depression, on the other hand, may have an adverse effect on development.

While prudent about taking prescriptions, women may be too lax when it comes to popping over-the-counter medications and herbal remedies. "Even some cold products can cause blood pressure to go up," warns Uhl.

Doctors are further handicapped by a lack of full disclosure on the part of their patients. Tim Tracy, professor of experimental and clinical pharmacology at the University of Minnesota, Twin Cities, tracked a large group of pregnant women and found they were taking many more medications than their obstetrician knew about. Ninety percent of the subjects self-medicated, usually for pain or colds.

Tracy explains, "It often didn't occur to the patients to report these, or chronic prescription medications, to their ob-gyn."

ON THE SAFE SIDE?:

3 Number of prescription drugs the average woman takes during pregnancy

6 Average number of prescription drugs taken by pregnant women over age 35

20% Percentage of pregnant women estimated to be clinically depressed

50% Percentage of unplanned pregnancies

SAFE: Peppermint or ginger for nausea

NOT NECESSARILY SAFE: Ibuprofen, aspirin, Pepto-Bismol, the herb black cohosh

Source: Food and Drug Administration. For more information, go to fda.gov and click on Women. The FDA lists registries seeking pregnant patients taking medications as well as a list of organizations that have information about the effects of medicines during pregnancy.