Fetoscopic Neural Tube Defect Repair

Inclusion Criteria:

* Maternal age 18 years or older
* Capable of consenting for their own participation in the study
* Decision to have fetoscopic repair following counseling of all options
* Open spina bifida with the upper boundary between T1 and S1
* Gestational age between 24 0/7 to 26 6/7 weeks' gestation at the time of surgery
* Normal karyotype and/or normal chromosomal microarray by invasive testing. In the case of a microdeletion, microduplication, or variant of uncertain significant, the decision to include or exclude will be at the discretion of the Principal Investigators.
* Absence of major cardiac anomalies confirmed by fetal echocardiogram
* Adequate social support throughout pregnancy
* Parental or guardian willingness to undergo follow-up evaluations of the child after birth

Exclusion Criteria:

* Multiple gestation
* Major fetal anomalies unrelated to the neural tube defect
* Kyphosis in fetus of 30 degrees or more as assessed by ultrasound or MRI
* Previous spontaneous singleton preterm birth prior to 37 weeks
* Presence of cervical cerclage at the time of surgery or history of cervical insufficiency
* Cervical length less than 20 mm by endovaginal ultrasound
* Placenta previa or evidence of placental abruption
* Technical factors such as large uterine fibroids, uterine anomalies, or fetal membrane separation for which the risks of surgery are deemed to outweigh the benefits
* Maternal obesity precluding surgical access with a BMI \> 45 or if the Principal Investigator determines the body habitus to be technically challenging
* Alloimmunization in pregnancy including Kell sensitization or a history of neonatal alloimmune thrombocytopenia
* Maternal HIV or Hepatitis B positive status. If the patient's HIV or Hepatitis B status is unknown, the patient must be tested and found to be negative prior to surgery
* Known Hepatitis C positivity. If the patient's Hepatitis C status is known, they do not need to be screened
* Maternal medical condition which is a contraindication to surgery or general anesthesia. This includes previous hysterotomy in the active segment of the uterus
* Maternal medical co-morbidities which would significantly increase the risk of spontaneous or iatrogenic preterm delivery
* Inability of the patient to comply with travel and follow-up requirements of the study
* Patient not meeting psychosocial criteria determined by fetal care social worked to comply with the medical care and plan for follow ups
* Participation in another interventional study that influences maternal and fetal morbidity and mortality
* Known history of hypersensitivity to collagen products or chondroitin materials