Medication in early pregnancy: prevalence of use and relationship to maternal characteristics.

Medication use was assessed in a population of 4186 women who were delivered of infants at Yale-New Haven Hospital, New Haven, Connecticut, between 1980 and 1982. The frequency of over-the-counter and prescription drug use, and the association of such use with maternal characteristics was studied. Of all women, 66% used at least one drug. The mean number of drugs used by all subjects was 1.3 and, among drug users, 2.9. Of all drugs used, 68% were over-the-counter and 32% were prescription preparations. Internal analgesics, autonomic drugs, antiinfective agents, and antacids were most frequently used. Women who used prescription drugs were also more likely to use over-the-counter medications. Maternal characteristics that were associated with an increase in both over-the-counter and prescription drug use were being white, smoking more than 20 cigarettes a day, using alcohol, using caffeine, and smoking marijuana. These findings suggest that women who engage in "risk-taking behavior" during pregnancy are also more likely to use medications while pregnant.