Prenatal exposure to paracetamol is linked to measurable differences in ovarian and uterine development in infant girls, according to a study published in Human Reproduction Open. Researchers at Copenhagen University Hospital tracked 685 pregnant women during their first trimester, finding that female infants exposed to the common analgesic exhibited reduced ovarian volume and lower follicle counts at three months of age compared to unexposed controls.
The Copenhagen Analgesic Study Findings
Conducted between March 2020 and November 2022 at Copenhagen University Hospital, the Copana study monitored pregnant participants using biweekly questionnaires and validated drug use through urine samples. Out of the cohort, doctors examined 302 infants at three months old via abdominal ultrasound and blood tests. According to the findings, female babies whose mothers took paracetamol showed a 40% smaller average ovarian volume, a 13% lower uterine volume, and 23% fewer ovarian follicles than the control group.
Furthermore, infants exposed during the first 17 weeks of gestation demonstrated significantly lower levels of anti-Müllerian hormone (AMH), which serves as a clinical marker for ovarian reserve. To determine if these variations persist, scientists cross-referenced their data with an independent group of women from the Copenhagen Mother-Child Cohort followed from infancy to adolescence. That secondary review associated prenatal exposure with reduced uterine volume at puberty and smaller ovaries during adolescence.
Scientific Interpretation and Limitations
The authors noted that the research is observational and does not prove a direct cause-and-effect relationship.
The study has reignited debate over clinical guidelines for pain management during pregnancy. Las recomendaciones sobre el uso de paracetamol durante el embarazo deben revisarse», stated De Geyter.
Other specialists advised caution regarding immediate changes to clinical practice. Franziska Denk, professor of neuroscience at King’s College London, told the UK Science Media Center that the results do not mean women should stop taking paracetamol when medically indicated, noting that the sample size remains relatively small given the number of outcomes evaluated. Stephen Burgess, professor of biostatistics at University of Cambridge, pointed out potential confounding factors, stating that mothers who took paracetamol may differ substantially from those who did not.
Regulatory bodies continue to support the drug’s use under specific conditions. The European Medicines Agency (EMA) previously affirmed that paracetamol can be used during pregnancy when necessary, while emphasizing that it should be taken at the lowest effective dose for the shortest possible duration. Health authorities consistently recommend that pregnant individuals consult a qualified medical professional before starting or altering any treatment for pain or fever.