Prenatal Surgery

More common than open surgery, closed-womb procedures are still rare enough to be practiced at only a few dozen specialized institutions. Sometimes these procedures are called "needle treatments." Since the first fetal blood transfusion in 1963, fetal transfusions have become one of the most accepted types of fetal therapy, although they are still uncommon. Transfusions can save the life of a fetus if the blood of the fetus and its mother are incompatible. In the case of Rh incompatibility, for instance, the antibodies in the blood of an Rh negative mother will attack the red blood cells of an Rh positive baby. Guided by ultrasound, the doctor inserts a needle through the mother's abdomen and injects compatible blood into the umbilical blood vessels. In a similar fashion, doctors use needles to deliver life-saving medications.

Sometimes twins fail to develop normally, and the poor health of one twin jeopardizes the life of the other, healthy twin. Left untreated, such pregnancies typically end with the death of both twins. In this situation, parents might permit the doctor to perform fetal surgery and terminate the abnormal twin in order to save the healthy twin. In a rare condition known as twin-twin transfusion syndrome, the blood circulation of the two twins is connected and one fetus lacks a brain and a heart. In a closed-womb procedure, surgeons have successfully used miniature instruments to tie a knot in the blood vessels linking the two twins. Although this kills the abnormal twin, the other twin is much more likely to survive.

Pregnancies that begin with triplets and quadruplets almost never result in the healthy birth of all the fetuses. Indeed, the mother risks miscarrying the entire pregnancy. In this situation, parents and surgeons may decide to reduce the pregnancy to twins in order to ensure the health of at least some of the fetuses. Unwanted fetuses are killed using a needle to inject potassium chloride into the fetal chest. This stops the heart from beating. Multiple pregnancies are becoming more widespread due to the use of fertility drugs and certain infertility treatments. So-called fetal reduction has therefore become a potentially more common procedure, but it remains highly controversial.