[Use of medicines before and during pregnancy: prevalence and associated factors]

This cross-sectional prospective nested cohort study aimed to assess the prevalence of use of medication before and during pregnancy and associated factors in women in a municipality in the countryside of Bahia State, Brazil. Data were collected with a structured questionnaire applied to pregnant women at their prenatal visits at health units. Prevalence rates for use of medication before and during pregnancy were 52.1% and 84.7%, respectively. The following were associated with use of medication before pregnancy: age ≥ 30 years, non-white skin color, first prenatal visit after the 1st trimester, and economic classes C/D/E. There was an increase in medication during pregnancy among women with ≥ 11 years of schooling, women with more than three prenatal visits, and those with some health problem. Pregnant women are exposed to medication before and during pregnancy, notwithstanding the lack of secure information to back the use of medicines during this phase; such use is associated with factors pertaining to prenatal follow-up, suggesting the need for more active participation by pharmacists in orientation and support for rational use of medicines.