Open Intrauterine Fetal Myelomeningocele Repair: Changes in the Surgical Procedure and Perinatal Complications during the First 8 Years of Experience at a Single Center.

INTRODUCTION: Open fetal myelomeningocele (fMMC) repair is nowadays a therapeutic option in selected cases. We aimed to evaluate changes in maternal and fetal outcome after fMMC repair during the first 8 years of experience at a tertiary referral fetal medicine center in Switzerland. -Materials and Methods: Between 2010 and 2018, fMMC repair and delivery of the neonate via planned cesarean section was performed in 67 cases. Cases were retrospectively stratified into 2 groups: a "training phase" (TP) with supervision from an external surgeon during 11 operations (2010-2014, 15 cases) followed by an "experienced phase" (EP, 2014-2018, 52 cases); each phase lasted about 4 years. Both phases were compared with regard to various maternal and fetal outcome parameters. RESULTS: Analyses did not reveal differences between TP and EP in major outcome parameters such as gestational age at delivery, chorionic membrane separation, or the incidence of placental abruption. Although more complex surgical techniques were applied in EP (e.g., dermal closure using a rotational flap), surgery time was not different from TP. At the same time, surgical complications such as oligohydramnios (27 vs. 8%, p = 0.046) with MRI-confirmed leakage (13 vs. 4%, nonsignificant) and subchorionic hematoma (20 vs. 2%, p = 0.009) were less common in EP than TP. CONCLUSIONS: This study shows that the level of competence at our center with regard to major perinatal outcome parameters was already high in the first years of fMMC repair. However, more complex surgical techniques and significantly less minor complications were observed during the most recent years.