6 PHOTOS Rare baby born completely in amniotic sac See Gallery Rare baby born completely in amniotic sac A California baby was born en caul, which means he came out of the womb still completely encased in his amniotic sac — a medical rarity. Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

A California baby, born prematurely at 26 weeks, is a true rarity.

This is 10-week-old Silas Phillips. He was born via cesarean section, completely enclosed in his amniotic sac, something known as being born 'en caul.'

Silas was born at Cedars-Sinai Medical Center in Los Angeles, which posted on Facebook that births like his only happen once in every 80,000. Luckily, little Silas is doing well.

Births en caul are rare because the amniotic sac tends to rupture before birth -- something that's commonly referred to as a woman's "water breaking" -- but especially when it comes to c-sections, because the scalpel generally punctures it.

When babies are born completely en caul, they still behave as though they were in the womb, and still take in oxygen through the placenta.

KCAL reports Silas's mother, Chelsea, didn't even realize he had been born en caul until a doctor showed her pictures hours later. Cedars Sinai said last week Silas is almost ready to go home.



Correction: An earlier version of this video said the baby was born 26 weeks premature. The video and the text in this article have been updated.





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