Adverse drug reactions in pregnant women: Do they differ from those in non-pregnant women of childbearing age?

Pharmacoepidemiological research in pregnant women has focused on adverse drug reactions for the course of pregnancy or for the unborn child, but little is known on the risks for the mother. We reported the results of a study that compared adverse drug reactions in pregnant women with non-pregnant women of childbearing age, and investigated whether which types of adverse reactions were more often reported in pregnant women and which drugs were more often involved. This study was carried out in the French pharmacovigilance database (BNPV). We compared adverse drug reactions reported between 1 January 2010 and 31 December 2019 in pregnant women with those reported in of non-pregnant women of childbearing age. We cross-matched each pregnant woman with three non-pregnant women of childbearing age according to geographic area, age and year the adverse reaction was reported. Data analysis revealed that serious adverse reactions were more frequently reported in pregnant women, including anaphylactic reactions. Other adverse reactions including tachycardia, hypotension and hepatic injury were also more frequent in pregnant women than in non-pregnant women of the same age. This could be explained by physiological changes in pregnancy that lead to greater sensitivity to certain adverse reactions. Some drugs, such as phloroglucinol, metoclopramide, iron, atosiban and nifedipine, were more frequently involved in adverse reactions in pregnant women. These drugs are specifically used during pregnancy, which may explain why they are over-represented in adverse reactions. This is the first comparative descriptive study on drug adverse reactions in pregnant women. Specific epidemiological and pharmacokinetic studies are necessary to confirm these results and better understand the differences observed to improve the monitoring of pregnant women exposed to certain drugs.