Introduction: Spina bifida (SB) is a severe neural tube defect affecting motor function, mobility, and quality of life. Prenatal repair has become the gold standard in selected cases, offering better outcomes than postnatal approaches. This study evaluated SB prenatal repair outcomes in a middle-income country, comparing our results with the Management of Myelomeningocele Study (MOMS) trial. It also reports the impact of routine use of uterine wound retractor on reducing uterine trauma and improving outcomes. Methods: This retrospective observational study analyzed 90 fetuses undergoing open prenatal SB repair between 2012 and 2024 at a single center in Chile. Inclusion/exclusion criteria followed the MOMS trial, later adjusted to include higher maternal body mass index (BMI) (n = 11) and gestational age at surgery >26 weeks (n = 12) based on emerging evidence. Clinical outcomes were assessed at 12 and 30 months postnatally and compared with MOMS trial results. Results: Our cohort had a higher maternal BMI, shorter cervical length, and more severe lesion level (L1–L4) than the MOMS trial. Maternal outcomes were favorable, with lower chorioamniotic separation (1% vs. 26%), oligohydramnios (4% vs. 21%), and preterm prelabor rupture of membranes (25% vs. 46%). Neonatal outcomes included more births ≥37 weeks (47% vs. 21%) but a greater proportion of low-birth-weight neonates <10th percentile (14% vs. 4%). At 12 months, ventriculo-peritoneal shunting was less frequent (33% vs. 40%) but not statistically significant. At 30 months, walking with orthesis was higher (48% vs. 29%), but independent walking was lower (13% vs. 42%). Conclusions: This study confirms the feasibility and effectiveness of open prenatal SB repair in a middle-income setting, with outcomes comparable and in some instances even better than the MOMS trial. Our results suggest that the combined use of a smaller hysterotomy and an atraumatic, low-cost, and widely available uterine wound retractor could significantly improve maternal and obstetric results. This is the largest cohort evaluating this approach in a single referral center.

Journal Section:
Fetal Therapy
Keywords:
Fetal surgery, Prenatal repair, Spina bifida, Wound retractor
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