Spina bifida is one of the most common and yet most severe of birth defects. It affects the central nervous systems of between 300,000 and 400,000 babies around the world. The most serious form of spina bifida occurs when the spinal cord protrudes through an opening in the spine.
Survivors often experience lifelong disabilities including paralysis, bladder and bowel problems, and excess fluid on the brain. Traditionally, surgery to repair this condition is done after birth. In recent decades, however, surgery to repair the opening has been done while the baby is in the womb. Now, a new study shows that some babies who undergo fetal surgery do better than those who do not. Details of the study, were published Wednesday in the New England Journal of Medicine.
Three years ago, little Josh Tolboe faced a life full of physical obstacles. His parents, McKay and Linda Tolboe, knew before his birth that he had Myelomeningocele, the severest form of a birth defect known as spina bifida. Linda got the news first from her obstetrician.
"She sat there with me and she told me he had what's called spina bifida, bilateral club feet and hydrocephalus [excess fluid on the brain]," Linda Tolboe recalled.
The condition is typically diagnosed during pregnancy, either by ultrasound or some other form of advanced testing. Eight days later, doctors placed a shunt in his head to relieve the fluid. So far, Josh has had seven surgeries on his back and spine.
Josh is now three years old and gets around in a red walker. His mother says another mother of a spina bifida child advised her to treat Josh the same way she treats his older brother Gavin.
"We don't help him in any way, unless he really needs it," Linda Tolboe added. "We treat him like anybody else."
Fetal surgery to repair birth defects has been performed for at least 30 years. But researchers wondered whether the prenatal procedure really could improve the outcome for those babies, and whether the risks for the baby and mother were worth overcoming. The scientists now say a randomized clinical trial of 183 pregnant women carrying spina bifida babies proved to be so positive that the study was stopped after two phases.
The researchers studied results at one year of age after the prenatal surgery. Fewer babies undergoing surgery in the womb had need for a shunt, compared to those who waited for surgery after birth. At 30 months, there was improvement in mental development and motor function.
Dr. Catherine Spong of the National Institute of Child Health and Human Development says more of the children in the prenatal study could walk without braces or orthotics than those who underwent surgery after birth.
"In the prenatal surgery group, 40 percent of the babies were able to walk independently, compared to about only 21 percent in the postnatal surgery group," noted Spong.
Dr. Spong says at least one-third of the prenatal surgical patients no longer had what's called hindbrain herniation, in which the base of the brain is pulled into the spinal cord.
"You were able to replace the spinal cord and allow a more normal development of the baby's brain," Spong added.
While these conclusions sound so optimistic, the doctors say there still are important issues to consider, especially since a majority of these babies were born prematurely.
"There are a number of complications associated with pre-term delivery: respiratory distress, where the baby has had difficulty breathing, they need to be intubated [a breathing tube inserted], a number of complications, and certainly you saw those in those preterm babies," Spong explained.
When Linda Tolboe was carrying Josh, she and her husband turned down the chance to have surgery done while he was in the womb. They said they were more concerned about the risk of premature birth, and opted instead for repairs to be made after delivery. Would she have changed her mind, knowing what she knows now?
"If I would have known that, I probably would have done something and would have said 'well, let's do it. Let's just see what happens with him,'" said Tolboe.
Dr. Spong says she does not question parents' reluctance to have the surgery done before birth. Before it is seriously considered, she says, make sure the doctors and hospital have a lot of expertise in caring for the baby and the mother.