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CME Credit Offered
CME Credit Offered
Abstract Award
Abstract Award
Recording available 2/16-5/2
Recording available 2/16-5/2
AIUM Credit
AIUM Credit
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Foundation Awardee
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Abstract Award
Abstract Award
Foundation Awardee
Foundation Awardee

Poster Session 4

Category: Clinical Obstetrics

Poster Session 4

(1138) Is the incidence of placental insufficiency increased after prenatal surgery for spina bifida?

Thursday, February 12, 2026
3:30 PM - 5:00 PM  
Objective:
Fetal open neural tube defects (ONTDs) affect 0.1% of pregnancies. Prenatal repair improves fetal outcomes but comes with a higher risk of preterm delivery (PTD). It is unclear if prenatal repair, or repair technique (fetoscopic or open via hysterotomy), lead to placental pathology that may increase the risk of PTD or obstetric complication. This study aims to compare pathologic markers of placental insufficiency in fetuses with repaired vs unrepaired ONTDs.

Study Design:
This is a retrospective cohort study of pregnancies with fetal ONTDs referred to a single fetal center between 2015 and 2024. The primary outcomes were maternal and fetal malperfusion scores, which are composite measures of placental parenchymal lesions associated with placental injury related to altered uterine and intervillous blood flow. Secondary outcomes included placental weight, delivery outcomes, birthweight, umbilical artery pH, Apgar score at 1 and 5 minutes, and NICU length of stay. Outcomes were compared between cases undergoing prenatal vs postnatal repair, as well as between repair type.

Results:
Of the 88 fetuses included, 42 underwent prenatal repair, while 46 underwent postnatal repair. Of the 42 prenatally repaired cases, 32 were repaired via hysterotomy, while 10 were repaired fetoscopically. Maternal characteristics, including age, parity, and chronic medical conditions did not differ across groups. Maternal and fetal placental malperfusion scores did not differ by prenatal vs postnatal repair cases (Table 1) or by surgical approach among prenatally repaired cases (Table 2). Gestational age at delivery was earlier in the prenatal repair group (36.1 vs 39.0 weeks, P < 0.01) but did not differ between type of prenatal repair (fetoscopic 35.7 vs hysterotomy 36.3 weeks, P = 0.70). There were no differences in placental weight percentile, birthweight percentile, or assessed neonatal outcomes amongst comparison groups.

Conclusion:
Prenatal repair of ONTDs is not associated with placental malperfusion. This suggests that the higher rate of PTD after prenatal repair is not driven by placental insufficiency.