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March 21, 2025 28 mins

We all think we know the story of pregnancy. Sperm meets egg, followed by nine months of nurturing, nesting, and quiet incubation. this story isn’t the nursery rhyme we think it is. In a way, it’s a struggle, almost like a tiny war. And right on the front lines of that battle is another major player on the stage of pregnancy that not a single person on the planet would be here without. An entirely new organ: the placenta.

In this episode, which we originally released in 2021, we take you on a journey through the 270-day life of this weird, squishy, gelatinous orb, and discover that it is so much more than an organ. It’s a foreign invader. A piece of meat. A friend and parent. And it’s perhaps the most essential piece in the survival of our kind.

Special thanks to Diana Bianchi, Julia Katz, Sam Behjati, Celia Bardwell-Jones, Mathilde Cohen, Hannah Ingraham, Pip Lipkin, and Molly Fassler.

EPISODE CREDITS: 
Reported by - Heather Radke and Becca Bressler
with help from - Molly Webster
Produced by - Becca Bressler
with help from - Pat Walters, Maria Paz Gutierrez

EPISODE CITATIONS:

Articles:
Check out Harvey’s latest paper published with Julia Katz.
Sam Behjati's latest paper on the placenta as a "genetic dumping ground". 

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