The role of prenatal, obstetric and neonatal factors in the development of autism.

Dodds et al. (2011) linked birth records to later autism diagnoses across Canada. They pulled 129 733 files to see if problems during pregnancy or birth predicted who later received an ASD label.

The team counted many maternal and obstetric events, then asked whether these events mattered more for kids with little family history of autism.

Most birth events showed only tiny links to autism. The effects were modest and depended on the child's genetic risk.

When family history of autism was low, some obstetric factors slightly raised the odds. When family history was high, the same factors added almost nothing.

Sievers et al. (2020) in Brazil extend the story: being born before 37 weeks carried 3.5 times higher odds of later ASD or ADHD. This tight focus on prematurity gives you a clearer, stronger signal than the broad Canadian sweep.

Weiss et al. (2001) seem to disagree. In kids with tuberous sclerosis—a high-genetic-risk group—mild birth complications had zero link to autism severity. The contradiction fades once you see that genes already set the course; birth events can't add much.

Lung et al. (2018) and Boudreau et al. (2015) confirm one part of Linda's picture: babies conceived through assisted reproductive technology were no more likely to be diagnosed with autism once parents' income and education were held constant.

When you talk with families, put birth events in perspective. Obstetric troubles may nudge risk a little, but they rarely cause autism on their own. Genetic load appears to set the ceiling. Use this to ease guilt—mothers did not