Although doctors have been able to perform surgeries on babies before their birth for the last 20 years, it has only recently become an option that could be practiced more frequently in the near future. Currently, the risky nature of a surgery to a pregnant mother and child has limited the use of this practice to only the direst of cases. When successful, however, surgeries of this type can be used to correct some severe problems such as spina bifida by surgically closing the hole through which the spinal cord mistakenly extends. Since doctors know that a majority of the problems caused by spina bifida occurs before the baby is born, repairing it during this stage can help to reduce side effects, paralysis and unwanted brain fluid1.
The reality of in utero surgeries are so risky, however, that there is some debate regarding which ones should be attempted. The hole resulting from spina bifida can be closed through surgery, as well as the hole caused by congenital diaphragmatic hernia (CDH). With CDH, the hole is in the baby’s diaphragm. This causes a problem since the organs that are supposed to remain in the abdomen can move upwards into the chest. This displaces the lungs and often causes the baby’s death soon after birth since the lungs have little room to develop properly. Unfortunately, when surgeons began trying to correct CDH while the baby was in utero, there were several problems. For example, if the liver had moved upwards into the chest, the blood flow could easily become compromised, killing the baby2. Even worse, fetal surgery of this sort which requires the mother’s abdomen to be opened raised the possibility of a premature delivery. Given these problems, movement towards a safer procedure to accomplish the same goals has become paramount.
It is hoped that with stem cell research and gene therapy, doctors may be able to decrease the risk inherent in fetal operations by combining these new therapies with less traumatic surgeries as well as increase the number of fetal diseases they are able to diagnose in utero and treat. In fact, some believe that surgeries requiring the mother’s abdomen to be opened in order to reach the baby will be completely replaced by stem cell or gene therapy within the next 20 years.
Dr. Dario Fauza, a surgery associate at the Children’s Hospital Boston, has found a way to separate the fetal stem cells from the amniotic fluid. Using these cells, doctors might be able to cause them to grow into tissue that would cover the hole. Although not currently possible, it is suspected to be achievable in the next 10 years. If this worked, it could quell the intense side effects sometimes seen from current fetal surgeries. Stem cell therapy of this kind is seen by many scientists as the future of medicine and very promising. By introducing the cells needed by the baby while in utero, it is thought diseases could be corrected before severe symptoms occurred. Furthermore, since the immune system of the baby would be weak, it would more easily accept such stem cells. Also, since the baby is still a small mass of growing and differentiating cells, introducing new stem cells at this point would allow them to integrate more fully and succeed more definitely.
Gene therapy, a second alternative to the current fetal surgery is interesting in theory however, in practice it has yet to progress as far as stem cell research has. This has been studied in mice, however, not in humans3. This type of therapy manipulates viruses to introduce a gene needed by the patient to their cells. For a developing baby, this may interfere with their development. Also, a foreign gene such as this could initiate an immune response which could be counterproductive. As such, gene therapy will most likely be used only in the most ominous of situations.
Spina bifida affects 1 in every 1,500 babies each year while CDH occurs in 1 of every 2,500. In the U.S., $230 million each year is spent due to CDH4. According to the Centers for Disease Control (CDC), $636,000 is spent for each baby born with spina bifida during their lifetime5. This is only a small fraction of the costs associated with the various diseases children can be born with. If the possibilities for stem and gene therapy come to fruition as many scientists believe they will, these costs can be reduced for both the families affected as well as the government.
1. Nature Medicine 14 (11), 1176-1177 (2008)
2. J. Pediatr. Surg. 32, 1637-1642 (1997)
3. Opin. Mol. Ther. 9, 432-438 (2007)
4. J. Pediatr. Surg. 30 (2), 226-230 (1995)