It's a disease called Twin to Twin Transfusion Syndrome, and one of the few places in the Midwest where it can be treated is the St. Louis Fetal Care Institute, run by Cardinal Glennon Children's Medical center out of its sister hospital, St. Mary's in Richmond Heights.

The condition happens when blood vessels of one identical twin to mistakenly merge with blood vessels from the other, causing a dangerous imbalance that is bad for both.

But at the new St. Louis Fetal Care Institute, doctors can use a thin scope to enter the womb, find the places where the blood vessels are growing together and separate them with a laser.


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It used to be 80% of twins with this condition died. Now, with this surgery, 80% survive it.

That surgery is available at only 22 hospitals in the United States, with St. Mary's in St. Louis being one of them.

An even more rare procedure involves removing the fetus from the mother, repairing the problem, and returning it to the womb. That surgery is available at only six U.S hospitals, including St. Mary's, thanks to the Fetal Institute.