Outcomes of late open fetal surgery for intrauterine spina bifida repair after 26weeks. Should we extend the Management of Myelomeningocele Study time window?

Abstract

To evaluate maternal and perinatal outcomes of late open fetal repair for open spina bifida (OSB) between 26+0 -27+6 weeks. A cohort of fetuses with OSB who underwent open surgery in two fetal surgery centers (Argentina and Mexico). Two groups were defined based on the gestational age (GA) at intervention: Management of Myelomeningocele Study (MOMS) time window group: GA 19+0 -25+6 , and late intervention group: GA 26+0 -27+6 . Intrauterine OSB repair was successfully performed in 140 cases, either before (n=57) or after (n=83) 26weeks, at on average 25+0 (22+6 -25+6 ) and 26+5 (26+0 -27+6 ) weeks + days, respectively. There were no significant differences in the rate of premature rupture of membranes, chorioamnionitis, oligohydramnios, preterm delivery, perinatal death and maternal complications. The late intervention group showed a significantly lower surgical times (112.6 vs. 124.2min, p=0.01), lower interval between fetal surgery and delivery (7.9 vs. 9.2weeks, p<0.01) and similar rate of hydrocephalus requiring treatment (30.6% vs. 23.3%, p=0.44) than the MOMS time window group. Late fetal surgery for OSB repair between 26+0 -27+6 weeks is feasible and was associated with similar outcomes than that performed before 26weeks. These findings may allow an extension of the proposed time window for cases with late diagnosis or referral.