Rare Blood Disorder Haunts Twins in Womb

July 29, 2008— -- After two and a half years of marriage, Kim and Nate Stroh of Humble, Tex., got the good news on New Year's Day that Kim was pregnant with twins.

"We were thrilled about having twins. It felt like it was something so special," Kim, 27, said.

Then, in mid-April, in the course of a routine ultrasound, doctors discovered that the twins were not fraternal, as Kim and Nate had been told, but identical. The Strohs were also told the pregnancy was in trouble. Doctors had discovered a deadly complication.

"To go from 'there's no problem' to 'you could lose them both' in about 10 minutes," Nate said. "It was like being hit by a bus."

"We just got on the couch and cried, and prayed," Kim said.

The twins were diagnosed with "Twin-to-Twin Transfusion Syndrome," which affects about 2,000 pregnancies every year. For reasons that are unclear, the blood flow between the twins becomes unbalanced. One fetus begins to take blood from the other.

The condition can occur in identical twins who share a placenta.

"All identical twins pretty much have connecting vessels," said Dr. Kenneth Moise, a specialist at the Texas Children's Fetal Center, who operated on Kim. "But one out of ten times does this syndrome manifest itself."

The fetus that receives more blood grows bigger and is at risk of heart failure due to the overworked heart. Conversely, the smaller baby does not receive enough blood, stunting its growth.

If left untreated, in 80 to 90 percent of the cases, both twins will die.

At the Texas Children's Hospital, specialists diagnose and treat Twin-Twin Transfusion Syndrome and handle about three cases each week.

Doctors, using new technology to work inside the mother's uterus, separate the blood vessels that connect the twins.

Kim, sedated but awake, underwent surgery during her 22nd week of pregnancy .

During the surgery, doctors entered the amniotic sack using a kind of miniature "telescope." Occasionally, to their surprise, a fetus will actually grab on to the scope in the middle of the procedure.