Fetal myelomeningocele surgery: Only treating the tip of the iceberg.

Abstract

Fetal myelomeningocele (fMMC) surgery improves infant outcomes when compared with postnatal surgery. Surgical selection criteria and the option of pregnancy termination, however, limit the number of cases that are eligible for prenatal surgery. We aimed to quantify what proportion of cases could ultimately benefit from fetal therapy. We retrospectively reviewed all cases of fMMC referred to a large tertiary care center over a 10-year period and assessed their eligibility for fetal surgery, pregnancy termination rates, and actual uptake of the surgery. Of 158 cases, 67 (42%) were ineligible for fetal surgery based on surgical exclusion criteria. Eleven fetuses (7%) had chromosomal anomalies, 10 of which (91%) had other anomalies on ultrasound. Thirty-four patients had a combination of maternal and fetal contraindications. Of the remaining 91 eligible cases (58%), 45 (49%) pregnancies were terminated, leaving only 46 (29% of initial 158 cases) as potential candidates for fetal repair. Actual uptake of fetal surgery was 15% (n=14 of 91), but this increased after a national program was started. Only a minority of fMMC cases will ultimately undergo fetal surgery. These numbers support the centralization of care in expert centers.