Maternal Inclusion Criteria: 1. Singleton pregnancy 2. Gestational age at screening is 19 to 25 5/7 weeks and gestational age at surgery is 22 to 25 6/7 weeks 3. Maternal age: 18 years and older 4. Body mass index ≤45 kg/m2 (pre-pregnancy) 5. No preterm birth risk factors (short cervix <20 mm or a history of previous preterm delivery) 6. No previous uterine incision in the active uterine segment 7. Willing to undergo an open fetal repair if the fetoscopic approach is unsuccessful Fetal Inclusion Criteria: 1. Spina bifida defect between T1 to S1 vertebral levels 2. Chiari II malformation 3. No evidence of kyphosis (curved spine) 4. No major life-threatening fetal anomaly unrelated to spina bifida 5. Normal karyotype, or a normal chromosomal microarray analysis (CMA), or a CMA with variants of unknown significance [fluorescence in situ hybridization (FISH) acceptable if ≥ 24 weeks].

Maternal Exclusion Criteria: 1. Non-resident of the United States 2. Multifetal pregnancy 3. Poorly controlled insulin-dependent pregestational diabetes 4. Poorly controlled A2 diabetes mellitus (A2DM) insulin-dependent diabetes 5. Current or planned cerclage or documented history of an incompetent cervix 6. Placenta previa or placental abruption 7. Short cervix of < 20 mm 8. Obesity as defined by a body mass index of > 45 kg/m2 9. Previous spontaneous singleton delivery prior to 37 weeks 10. Maternal-fetal Rh isoimmunization, Kell sensitization, or a history of neonatal alloimmune thrombocytopenia 11. HIV or Hepatitis-B positive status 12. Known Hepatitis-C positivity 13. Uterine anomaly such as large or multiple fibroids or a mullerian duct abnormality that is diagnosed via imaging prior to surgery, which that are unavoidable during surgery 14. Other medical conditions which are contraindication to surgery or general anesthesia 15. Patient does not have a support person 16. Inability to comply with the travel and follow-up requirements of the trial 17. Patient does not meet psychosocial standardized assessment criteria 18. Participation in this or another intervention study that influences maternal and fetal morbidity and mortality 19. Maternal hypertension 20. Zika virus positivity 21. Allergy/history of drug reaction to Amphotericin B Fetal exclusion criteria: 1. Major fetal anomaly not related to spina bifida 2. Kyphosis in the fetus of 30 degrees or more 3. Ventriculomegaly greater than 15 mm and no movements noted at hip and knee joints