New Study Examines Impact of In-Utero Spina Bifida Surgery on Preterm Labor

A new study is offering a clearer look at risks and benefits patients and babies might face after myelomeningocele repair, allowing for better patient counseling. Colorado Fetal Care Center’s Michael Zaretsky, MD, teamed up with dozens of doctors from around the world to analyze 13 years of data on myelomeningocele (MMC), the most severe form of spina bifida. This project was made possible by the North American Fetal Therapy Network, an association that helps hospitals share data.

Doctors typically offer qualifying patients facing a myelomeningocele diagnosis the option of fetal surgery to improve the baby’s quality of life. This intervention can lead to a reduction in ventriculoperitoneal shunt rates, increased motor function and a higher likelihood for independent movement later in life. The main risk of opting into this in-utero surgery is the increased likelihood of preterm delivery. Dr. Zaretsky and his team wanted to understand exactly how high that risk is for both the pregnant patient and the baby.

The study uncovered three main findings to offer patients more concrete data:

• After in-utero spina bifida repair, preterm delivery prior to 30 weeks of gestation occurs in about 9% of patients. Research has not yet been able to identify what circumstances might lead to this early delivery. Of those patients that deliver before 30 weeks’ gestation, the data showed a 21% perinatal mortality rate for the baby.
• Preterm deliveries before 30 weeks' gestation had increased maternal and neonatal morbidity. Pregnant patients who deliver that early are more susceptible to infection, the need for blood transfusions and placental abruption.
• Regardless of how early the patient delivers, the ventriculoperitoneal shunt rates remained steady, showing that there are indeed benefits of the surgery.

“The data is very clear in the paper,” Dr. Zaretsky says. “Before, we didn’t have enough information or data to say if you can still derive any benefits from fetal surgery even if you deliver preterm. But now you can pull out the paper and show your patients. They get the information they need to make an informed decision.”

The team at the Colorado Fetal Care Center has performed more than 135 MMC surgeries since 2012, and a majority of the patients who received prenatal MMC repairs were able to return home to deliver at their home hospital. None of the babies who received fetoscopic MMC repair required shunts, which is well below the 40% benchmark.

Dr. Zaretsky notes that they still need data to explore how preterm delivery impacts independent ambulation and neurodevelopmental outcomes. He says that the next major area of research should explore how doctors might be able to lower the risk of preterm delivery for patients who undergo myelomeningocele repair.

MMC repair options

Since the Colorado Fetal Care Center opened in 2010, Children’s Colorado has offered the traditional open fetal procedure, achieving top outcomes. Children’s Colorado is among a few hospitals in the country and the only one in the seven-state region to offer this leading-edge fetoscopic MMC repair surgery to patients.