How Fetal Surgery Can Save a Baby's Life

September 11, 2023

Pregnancy woman in hospital gown holding belly

Pregnancy is an exciting time for families, but it can be stressful when a complication puts mom or baby at risk. Fortunately, new techniques in fetal surgery can offer hope.

“By providing advanced therapies during pregnancy, we aim to improve outcomes for mothers and babies with these types of complications.” says University Hospitals maternal fetal medicine specialist and pioneer of interventional fetal therapy, Giancarlo Mari, MD.

When Is Fetal Surgery Necessary?

Fetal surgery and other therapies can be used to treat many different conditions that can be life-threatening to babies in the womb. These include spina bifida, fetal anemia, fetal growth restriction, congenital heart defects and other defects affecting the baby’s vital organs.

Twin pregnancies in particular have a higher potential for complications. One rare but serious condition that can occur is twin to twin transfusion syndrome, or TTTS. This condition causes uneven blood flow between twins that share a placenta, called a monochorionic pregnancy – which includes nearly 70 percent of identical twins.

What Causes Twin to Twin Transfusion Syndrome?

When identical twins share a placenta, there are connections between the arteries and veins of the twins. Most of the time, there is nothing to worry about.

For reasons that are unknown, sometimes the connections between the blood vessels become unbalanced. TTTS is diagnosed when one of the twins has too much amniotic fluid in its gestational sac and the other twin has too little. This can cause the baby with less fluid to grow slower and produce less urine and the baby with too much fluid may develop high blood pressure.

TTTS occurs in about 10 to 15 percent of pregnancies where identical twins share a placenta. Experts aren’t sure what causes TTTS, but believe that it is not genetic or environmental, and it isn’t caused by anything that the mother does during pregnancy, says Dr. Mari.

What Are the Treatment Options for TTTS?

In the past, there were few treatments and little hope for severe cases of TTTS, which would often lead to the death of one or both twins. Today, there are options for treating TTTS, including the use of laser therapy while babies are still in utero.

Depending on the severity of the TTTS, some women can be managed with careful monitoring. In other cases, the care team may remove excess amniotic fluid from one baby’s gestational sac in a procedure called amnioreduction. In more severe cases of TTTS, laser ablation surgery is often recommended. This minimally invasive procedure is FDA approved for use from 16 to 26 weeks gestation.

With laser ablation, a small instrument called a fetoscope guides a camera, suction tube and laser through a small incision in the mother’s abdomen and into the uterus. The surgery team will map out the abnormal blood vessel connections in the placenta and use the laser to seal off those blood vessels. Then the excess amniotic fluid in one baby’s sac is drained through the suction tube.

Fetal laser ablation therapy can be done within days or even hours of a TTTS diagnosis, says Dr. Mari. It is usually performed while the mother is under sedation, and neither the mom nor the babies will experience any discomfort during the procedure. Patients can usually return home the day after the procedure. A follow-up ultrasound will be performed about a week after the procedure, and the pregnancy will continue to be monitored closely up until the babies are born.

Are There Side Effects From Fetal Laser Therapy?

Fetal laser therapy has been in use for nearly two decades. While the success rates vary depending on where the procedure is performed, it is still considered the best therapy currently available for TTTS with better outcomes than other treatments. There is still a risk of fetal death of one or both babies with laser therapy, but that risk is much smaller compared to that of other treatments or no treatment, Dr. Mari notes.

Intervention for Other Fetal Conditions

In addition to fetal laser therapy for TTTS, the fetal intervention program at UH has expertise in diagnosing and treating a number of other pregnancy complications. These include other twin conditions such as twin anemia polycythemia sequence (TAPS), twin reversed arterial perfusion sequence (TRAP), and selective fetal growth restriction.

Dr. Mari has performed laser therapy for 20 years and has trained doctors in fetal intervention techniques both in the U.S. and abroad. He says having a top fetal center in Northeast Ohio is so valuable for expecting families.

“Area women who experience pregnancy complications no longer have to travel to receive life-saving care for their babies,” says Dr. Mari. “As a comprehensive center, we can offer these procedures to both patients in Northeast Ohio and those from other states as well.”