09/30/2026
The COPANA study found associations between acetaminophen exposure during pregnancy and certain measurements of reproductive development in female infants and adolescents. The findings are worth paying attention to, especially because they add to questions that deserve more research.
But association ≠causation. And the study did not measure infertility, pregnancy rates, age at menopause, or reproductive outcomes in adulthood.
There are also important limitations—including small numbers for some measurements, difficulty measuring infant ovaries, a relatively narrow study population, and the possibility that the illness prompting acetaminophen use contributed to the findings.
So what do we do with this information?
We keep studying it. We don’t dismiss concerning findings—but we also don’t turn preliminary evidence into conclusions that the research hasn’t established.
And importantly: acetaminophen remains the preferred medication for pain and fever during pregnancy when medication is needed. Untreated fever and significant pain also carry potential risks, so the answer isn’t simply “avoid all medication.”
If you’re pregnant and dealing with pain or fever, talk with your OB/midwife. ❤️