Prescribing any medication to a pregnant woman is a serious matter and could compromise both her health and the health of her fetus. But medications may be necessary because the benefits of keeping the woman healthy offset the risks. However, a study has found that four out of five pregnant women are given a prescription and that more than 40% of them may be prescribed a drug that could harm their fetus.
The study looked at the types of medications prescribed or taken and the time during pregnancy when they were used in a group of pregnant women who were on Medicaid before they became pregnant. Their analysis included over-the-counter medications given out by a pharmacist, but not meds purchased over the counter directly or prescribed during hospitalizations.
The researchers determined the 20 most common prescription medications overall and the 10 most common that were classed as either category D or X. Category D drugs means there is evidence they poses a risk to a fetus. Category X drugs means that tests in animals or humans have shown them to cause problems with the fetus. These categories are determined by the U.S. Food and Drug Administration, but the FDA now uses a different pregnancy risk categorization system that includes more information about a drug's risks during pregnancy. The FDA changed the way it labels medications in June, but these categories were in use when the study was conducted.
Researchers from the University of California, San Diego, found the most commonly prescribed medications are antibiotics used to treat infections. They also found that prescription medications are more likely to be given to younger pregnant women and to white women. However, they also found that 42% of the women were given a prescription for a category D or X drug during pregnancy.
For many drugs there is very little known about their effects during pregnancy. Many of the most commonly dispensed medications have limited or low-quality data available, the researchers say.
The study was published in the journal Obstetrics & Gynecology.