Open fetal surgical repair versus standard postnatal repair for myelomeningocele diagnosed at 20–26 weeks’ gestation: a systematic review and meta-analysis of shunt-dependent hydrocephalus, motor outcomes, and maternal morbidity

Objective: To assess shunt-dependent hydrocephalus by 12 months, motor function at two years, and maternal morbidity among hydrocephalus requiring shunt by 12 months, motor function at 2 years and maternal morbidity using open fetal repair and standard postnatal repair of myelomeningocele in fetuses diagnosed between 20-26 weeks gestation. Methods We searched MEDLINE, Embase, Cochrane CENTRAL and ClinicalTrials.gov through November 30, 2024. Eligible studies (1 RCT + 4 cohorts; n = 362 fetuses) reported shunt rates by 12 months, 2-year motor scores and maternal complications. RoB 2 (RCT) and ROBINS-I (cohorts) was used to assess risk of bias. Random-effects meta-analysis was performed and pooled risk ratios (RR), standardized mean differences (SMD) and odds ratios (OR) were calculated. Heterogeneity was assessed using I² and Tau². Sensitivity, subgroup and small-study–effect analyses were performed. Results Open fetal repair had half as many shunt dependencies (prenatal 87/211 = 41.2% vs. postnatal 215/242 = 88.8%; RR 0.55, 95% CI 0.45-0.68; I² = 30%, Tau² = 0.010). In terms of motor outcomes, prenatal repair was favored (SMD 0.75, 95% CI 0.50-1.00; I² = 25%, Tau² = 0.007). Maternal major morbidity was increased (OR 3.20, 95% CI 2.00-5.10; I² = 40%, Tau² = 0.020). Excluding high-risk cohorts marginally shortened CIs but did not affect estimates. Egger's test showed no evidence of bias for shunt (p=0.18) and motor scores (p=0.12), but moderate asymmetry for maternal harms (p=0.04). Conclusions Open fetal myelomeningocele repair at 20–26 weeks reduces shunt dependence and improves 2-year motor function; However, maternal risk of complications are three times higher. Treatment is recommended in specialized centers with multidisciplinary teams and thorough patient counseling.