Prenatal Tylenol use linked to organ changes

A new study published in the journal Human Reproduction Open suggests a potential link between acetaminophen, commonly known as Tylenol or paracetamol, use during pregnancy and altered reproductive organ development in daughters and sons. Researchers found that infant girls exposed to the pain reliever in utero had smaller ovaries, fewer ovarian follicles, and smaller uteruses compared to those not exposed. Infant boys exposed prenatally also showed reduced testicular volume on average. The study, which involved hundreds of infants and followed some girls into adolescence, emphasizes that it is observational and does not establish a direct cause-and-effect relationship. Led by Margit Bistrup Fischer of Rigshospitalet in Copenhagen, Denmark, the research examined 302 three-month-old baby girls whose mothers' acetaminophen use during pregnancy was tracked. The findings indicated that girls exposed in utero had, on average, 40 percent smaller ovarian volume, 13 percent smaller uterine volume, and 23 percent fewer ovarian follicles, which are structures containing immature eggs.