Introduction: Despite undoubtable benefits of open fetal myelomeningocele (fMMC) repair, there are considerable maternal risks. The aim of this study was to evaluate and systematically categorize maternal complications after open fMMC repair. Methods: We analyzed data of 40 fMMC repairs performed at the Zurich Center for Fetal Diagnosis and Therapy. Maternal complications were classified according to a 5-level grading system based on a classification of surgical complications proposed by Clavien and Dindo. Results: We observed no grade 5 complication (death of a patient). Five (12.5%) women demonstrated severe grade 4 complications: 1 case of uterine rupture in a nullipara at 36 gestational weeks (GW), a third-degree atrioventricular block which needed short mechanical resuscitation, a bilateral lung embolism requiring intensive care unit (ICU) management due to low-output syndrome, and chorioamnionitis and urosepsis both requiring ICU management at 31 GW. Twenty-six (65%) women had minor (grade 1–3) complications. Conclusions: Only one grade 4 complication (uterine rupture, 2.5%) was a clear-cut direct consequence of fetal surgery. The other four grade 4 complications (10%) occurred in the context of, but cannot unequivocally be attributed to, fetal surgery, since they may occur also in other circumstances. The classification system used is a tenable step towards stringent documentation of maternal complications.