Maternal outcomes following prenatal spina bifida repair: A systematic review and meta-analysis

Prenatal surgical interventions for neural tube defects have been shown to improve fetal outcomes but are associated with previously poorly quantified maternal risk, which is inherently dependent on the surgical approach used. We hypothesized that a meta-analysis would enable objective quantitation of maternal risk and safety, stratified by which antenatal neural tube defect surgical approaches were employed.

We conducted a meta-analysis by searching PubMed, Scopus, Embase, and Web of Science databases. We included all studies that performed prenatal intrauterine neural tube defect repair, regardless of the surgical technique. Our primary safety measure outcomes were maternal mortality and severe maternal morbidity (inclusive of uterine rupture or dehiscence, blood transfusion, and pulmonary edema). A total of 26 studies published between 2010 and 2024 were selected, prioritizing larger sample sizes and relevant outcomes when populations overlapped. The meta-analysis was conducted using random-effects models to account for between-study heterogeneity, which was quantified using the I ² statistic; sensitivity analyses and meta-regression were performed to assess robustness and explore sources of heterogeneity. Analyses were conducted using R software (version 4.0.5).

Our meta-analysis included a total of 1485 patients. No occurrence of maternal mortality was reported in any included studies (0/995). Some studies provided comprehensive data for all complications, while others only reported specific outcomes, leading to variation in case denominators: uterine rupture or dehiscence was observed in a pooled proportion of 4% (95% confidence interval [CI], 1%-11%), occurring in 7.4% of open surgery cases (53/710), 3.1% of mini-hysterotomy cases (6/192), and 0% of fetoscopic cases (0/157). Among 872 reported cases, maternal pulmonary edema occurred in 3% (pooled estimate: 0.03; 95% CI, 0.02-0.06). The lowest rate of pulmonary edema was seen with open surgical approaches (20 of 661 cases, 3%), followed by mini-hysterotomy (2 of 55 cases, 3.6%) and fetoscopic surgeries (15 of 159 cases, 9.4%). Model-adjusted pooled proportions demonstrated an overall low rate of maternal blood transfusion at 0.03 (95% CI, 0.01-0.05) among 971 cases.

This study highlights the need for standardized and comprehensive reporting of maternal outcomes in fetal surgery in order to reliably counsel patients on anticipated and acceptable maternal risk. However, despite limited data, our findings suggest that maternal mortality is rare and that severe maternal complications occur infrequently; however, the potential for serious morbidity underscores the need for careful patient selection, counselling, and standardized outcome reporting.