Reacción a "Researchers are investigating the link between paracetamol use during pregnancy and possible abnormalities in the reproductive development of baby girls"

This study requires extremely cautious interpretation.  The study design means it’s impossible to make any causal claims.  The small sample size and large numbers of outcomes make false positive findings very difficult to distinguish from any potential true effect.  We cannot conclude from this study that paracetamol is causing these effects.

When you hunt really hard for a pattern you inevitably find one.  I am worried that the authors are over-interpreting the one they found.  They set six primary outcomes – that gives you a 25% chance of false positives right off the bat.  And it gets worse with secondary outcomes without even considering causation, biological plausibility, effect magnitude or the heterogeneity of individual responses.

I am very concerned that this exploratory study will be misinterpreted.  Pregnant women already have a limited choice of pain medication, and paracetamol has an extremely high safety profile.  They should not conclude from this study that paracetamol will harm their child.