(30) Prenatal Surgical-to-Delivery Interval and 30-Month Neurodevelopment: A Secondary Analysis of the MOMS Cohort

To evaluate the impact of the prenatal surgical-to-delivery interval—the time between prenatal fetal myelomeningocele (fMMC) repair and delivery—on childhood neurological outcomes up to 30 months of life (MOL).

Study Design:

This was a secondary analysis of the prenatal fMMC repair arm of the Management of Myelomeningocele Study using data provided by the National Institutes of Health (NIH). The primary exposure was the surgery-to-delivery interval, dichotomized into the lowest quartile (58.2 days) and all others (58.2-110 days). The outcomes were perinatal death, need for shunt by 12 months of life (MOL), walking independently, the difference between anatomic and motor levels, Bayley II, Peabody, and WeeFIM scores. Bivariate analyses were performed using Fisher's and Wilcoxon tests. Linear regression was used to assess associations between surgical-to-delivery interval and Bayley scores, with adjustment for covariates.

Results:
90 participants were available for analysis, n=23 (25.5%) in the lowest quartile and n=67 (74.5%) in the higher quartiles. At 30 months, children in the shorter interval group had lower Bayley mental (82.9 [14.7] vs. 91.4 [14.7], p=0.02) and psychomotor scores (54.6 [11.2] vs. 67.2 [17.9], p=0.002), worse motor function relative to lesion level (p=0.02), and were less likely to walk independently (23.8% vs. 50.8%, p=0.05). After adjusting for preoperative ventricular size and accounting for collinearity with gestational age via residual analysis, longer surgical-to-delivery interval remained significantly associated with higher Bayley mental scores (adjusted coefficient: 0.24 [95% CI: 0.07, 0.41], p=0.005).


Conclusion:

A shorter interval between prenatal fMMC repair and delivery is associated with worse neurodevelopmental outcomes in some domains at 30 months. Notably, this association persists even when accounting for gestational age at delivery, indicating that the duration of pregnancy following fetal surgery exerts an independent effect. These findings emphasize the dual importance of prolonging gestation after intervention and carefully selecting the timing of surgery.