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.
"The fetus will reach up and wonder what this scope is," Moise said. "And even though his or her eyes are fused so they can't really see the scope, they'll grab the scope sometimes because it's an object in their cavity."
In Kim's case, working inside her womb, Moise sealed 14 blood vessels to prevent the blood from passing between the twins.
"The laser actually sends a beam of light very close to the blood vessel and creates heat on the blood vessel and it shrinks down and closes completely," Moise said.
"Identifying every vessel that's there and sorting out the good vessels from the bad vessels" is the most difficult challenge.
After the surgery was complete, all Kim and Nate could do was wait and pray. The procedure improves a couple's odds, but it's not a guarantee. Twenty percent of those who receive surgery will lose the fetus.
Two months later, 32 weeks into her pregnancy, Kim gave birth.
"I was proud because they were my babies," Kim said. "But I was proud because I knew what they had come through and how much they had fought to be there."
Owen was born weighing 4 pounds, 6 ounces and Blake, the smaller twin, weighed only 2 pounds, 6 ounces.
Although they are "tiny," the boys' prognosis is good. Doctors expect that they will leave the hospital within a few weeks.
"When I hold them I think I almost didn't get to have this moment with you guys," Kim said. "I almost didn't get to hold them…They almost weren't here."