Fetal spina bifida repair in obese mothers: is maternal and fetal safety warranted?

Introduction The MOMS-trial eligibility criteria preclude in utero surgery for fetal spina bifida (fSB) when maternal body mass index (BMI) is≥35 kg/m2. Some centers still respect this criterion while others, like ours, do not. This study aims to assess whether maternal and fetal safety are warranted with higher maternal BMIs.

Material and Methods Data of 192 patients with open fSB repair at our center were retrospectively analyzed. According to their BMI, patients were divided into three different groups; group 1 (BMI<30 kg/m2), group 2 (BMI 30-35 kg/m2) and group 3 (BMI>35 kg/m2). Subgroup analysis was performed to assess differences in maternal and fetal outcomes. Additionally, complications were divided into grades 1 to 5 according to their severity and outcome consequences and compared among groups.

Results Out of 192 patients, 146 (76.0%) had a BMI<30 kg/m2, 26 (14.6%) had a BMI 30-35 kg/m2, and 18 (9.4%) had a BMI>35 kg/m2. Significant differences occurring more often in either group 2 or 3 compared to group 1 were: maternal wound seroma (50% or 56% vs. 32%, p=0.04), amniotic fluid leakage (14% or 6% vs. 2%, p=0.01) as well as vaginal bleeding (11% or 35% vs. 9%, p=0.01). On the contrary, duration of tocolysis with atosiban was shorter in patients with BMI>30 kg/m2 (4 or 5 vs. 6 days, p=0.01). When comparing severity of maternal or fetal complications, intervention-related complications grade 1 occurred significantly more often in group 3 compared to group 1 or 2 (78% vs. 45% or 57%, p=0.02). Gestational age at delivery was around 36 weeks in all groups without significant differences.

Conclusion This investigation did not identify clinically relevant maternal and/or fetal outcome problems related to BMIs>35 kg/m2. Thus, we plea for judicious flexibility regarding this eligibility criterion.

Publication History

Article published online:
15 November 2023