Acetaminophen and pregnancy: common exposure, potential placental impact.

Acetaminophen (acetaminophen, APAP), alternatively referred to as paracetamol, is generally accepted as a safe pharmacologic choice to treat pain and fever during pregnancy. This review examines the prevalence and patterns of acetaminophen use during pregnancy and the historical context behind this widespread use. We discuss the emerging and controversial data linking acetaminophen use during pregnancy and adverse effects on the fetus and offspring. Furthermore, we draw on mechanistic evidence from preclinical studies and observational clinical studies that support the hypothesis that in addition to the fetus and newborn, there is a potential impact of acetaminophen on the placenta. We draw on mechanistic data from pre-clinical experiments and observational data from clinical studies to assess the association between APAP exposure and placental cellular injury, preeclampsia, and growth restriction. We conclude that additional research is needed to ensure the most informed pharmacologic management of pain and fever during pregnancy.