Fact-check: "40 recorded cases in human history" of postpartum psychosis

A podcast claimed there have been "like 40 recorded cases in human history" of postpartum psychosis. We rate that false — truth score 0.03, confidence 0.96.

The claim aired on Timothy Gordon Rules for Retrogrades, one day after the mistrial in the Lindsay Clancy case, while the Plymouth County DA is still deciding whether to retry.

We steelman it first, because there is something real underneath. The legal point is defensible: the US has no infanticide statute, insanity standards vary by state and are hard to meet, and successful postpartum-psychosis insanity defenses genuinely are uncommon in American case law. The condition is also not a standalone DSM-5 diagnosis, and "puerperal insanity" was removed from British diagnostic categories in 1906. There is a real historical seam here.

But the sentence made a claim about a disease, not about case law. Population-based incidence runs 1 to 2 cases per 1,000 live births (systematic review range 0.89–2.6). Cleveland Clinic puts that at roughly 320 to 9,400 US cases per year — the most conservative figure in that range is eight times the speaker's total for all of human history, in one American year. Louis-Victor Marcé published the first textbook on postpartum psychiatric disorders in 1858; "puerperal insanity" accounted for roughly 6–10% of female admissions across nineteenth-century British public asylums; Danish registries track cohorts of 400,000 to 789,000 births; the UK maintains 22 dedicated inpatient Mother and Baby Units.

We take no position on whether Lindsay Clancy had postpartum psychosis. Prosecution expert Dr. Avram Mack testified he found no evidence of it; the jury deadlocked 11–1 over seven days. The claim we are checking is not about her.