Help for rare issue affecting in utero identical twins

It’s natural for twins to share inside the womb, however, sometimes things can get complicated. One such example is a condition called twin-to-twin transfusion syndrome, which can be extremely dangerous for identical twins in utero. Identical twins share the same placenta, and in turn they also share blood connections. Twin-to-twin transfusion syndrome occurs when some of those connections cause an unequal flow of blood to the twins. One infant gets too much blood, putting a strain on its tiny heart. The other infant gets too little blood and doesn’t grow as expected.

“The syndrome affects 10 to 15 percent of twins that are in separate sacs (diamniotic) but share a placenta (monochorionic),” says Dr. Barbara Parilla, a maternal-fetal medicine specialist at Advocate Lutheran General Hospital in Park Ridge, Ill. “It is important that women be aware of the warning signs because early diagnosis is one key to intervening successfully.”

If a woman is expecting identical twins that share a placenta, there can be some warning signs of the syndrome. These include:

• A feeling that there has been rapid growth in the womb
• Abdominal pain or tightness
• Excessive weight gain and swelling
• When measured, the uterus is bigger than it should be based upon your due date.

If your twins share a placenta, regular ultrasound scans are recommended every two weeks between 16 and 26 weeks of pregnancy. If a problem is suspected, you should be referred to a fetal medicine specialist for treatment.

Twin-to-twin transfusion syndrome can be treated. One option when the syndrome is considered mild is to drain amniotic fluid from the sac where there is too much liquid.  Another option in more severe cases is to use a laser beam to seal off the shared blood vessels.

“At Advocate Lutheran General Hospital, we offer laser therapy for twin-twin transfusion syndrome,” adds Dr. Parilla. “The procedure is performed through a small fetoscope, which is 2mm in diameter.”

Most twins with this syndrome deliver early, before 37 weeks. In some cases, the problem is not diagnosed until very late in the pregnancy, so experts suggest finding a hospital with a robust fetal medicine program.