Your Period Blood Has a Weird Origin Story: Spiral Arteries, Uterine Milk, and Monkey Eyeballs

Your Period Blood Has a Weird Origin Story: Spiral Arteries, Uterine Milk, and Monkey Eyeballs

From CRAMPED by Kate Downey

May 8, 2026 · 16 min · Season 2 · Episode 29

About this episode

This episode explores the origins of period blood, including the role of spiral arteries and new tissue growth in the uterine lining.

PATREON-ONLY EPISODE TEASER Join the CRAMPED Patreon (even at the free tier!) to listen to the full episode: https://patreon.com/cramped I started research for a totally normal episode about spiral arteries in the uterine lining, and SHIT GOT WEIRD. Get ready for a deep dive into where period blood comes from, all the new organs and tissue you grow every month, and how science got the info on how it all works. CRAMPED episodes are intended for informational and entertainment purposes only, and are not medical advice. See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info .

People in this episode

Host: Kate Downey

Topics covered

  • period blood
  • spiral arteries
  • uterine lining
  • science
  • health

Keywords

  • period blood
  • spiral arteries
  • uterine milk
  • science
  • health

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