INTRODUCTION: There is in Brazil a growing use of industrially produced medicines even during the female reprodutive cycle. During pregnancy two organisms are exposed to the effects of medicines but in the foetus this may result in toxicities with possible irreversible lesions. The present study aims at verifying the prevalence of the use of medicines during pregnancy in the studied population and its relationship with maternal characteristics, the pharmacological groups used and the source of prescription. METHODS: The use of medication was evaluated among 1,620 women that gave birth in five public, private and contracted hospitals in the city of S. Paulo between July and September 1993. RESULTS AND CONCLUSIONS: The relation between maternal schooling and kind of assistance in hospitals has revealed social inequality in the access to the several kinds of delivery assistance services. The prevalence of use of at least one medicine was 97.6% with an average of 4.2 drugs per woman. The prevalence of use of drugs by medical prescription and self-medication were 94.9% and 33.5%, respectively. The most used medications, excluding vitamins, mineral salts and vaccines, were analgesics, antacids, antispasmodics and antemetics. Users of the largest number of medicines were, characteristically, over 29, married, of university level, salaried workers and had access to private health services. Medical assistance had a facilitating role in access to the use of drugs during the gestational period of the population studied. Women need to be made aware of the potential risks they expose their foetuses to when using so many medicines. Physicians should reflect on their role in contributing to the solution to this problem.
Pregnancy; Drug use habits; Drug toxicity