Epidurals: Are labor epidurals really linked to autism?

About this episode

The episode explores the potential link between labor epidurals and autism, examining the evidence and statistical methods involved.

Epidurals are widely used and widely trusted for pain relief during labor. So when a 2020 study reported that they might be linked to autism, it raised a troubling question: could a routine medical decision have long-term consequences? We follow that claim from headline to evidence—and watch what happens when other scientists take a closer look. We dig into the original study, a wave of replication studies from around the world, and a meta-analysis that tries to make sense of it all. Along the way, we unpack hazard ratios, Cox regression, inverse probability weighting, and sibling analyses—and why even sophisticated statistical adjustment can’t eliminate confounding. Plus: why bigger datasets don’t solve everything, what happens when results shrink after adjustment, and how a controversial study turned into a case study in science working as it should. Bonus: our first guest journalist interview! Statistical topics Confounding Cox regression Hazard ratios Inverse probability weighting (IPTW) Multivariable adjustment Observational studies Residual confounding Retrospective cohort studies Sibling analysis Statistical adjustment Statistical significance vs practical significance…

People in this episode

Hosts: Regina Nuzzo, Kristin Sainani

Topics covered

• epidurals
• autism
• statistical analysis
• confounding
• replication studies
• medical decision-making

Keywords

• epidurals
• autism
• statistical adjustment
• confounding
• replication studies
• hazard ratios
• Cox regression
• inverse probability weighting

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