MMC Fetal Surgery Outcomes
Fetal Surgery for Spina Bifida: Outcomes at CHOP Following the MOMS Trial
Since 1995, Children’s Hospital of Philadelphia has been at the forefront of understanding, diagnosing and treating myelomeningocele (MMC), the most serious form of spina bifida, before birth. One of three clinical centers to participate in the seven-year Management of Myelomeningocele Study (MOMS), we have the greatest depth of collective experience — in both the fetal surgery and all aspects of care surrounding the condition — in the world.
The information shared here compares our experience with fMMC since the MOMS results were announced in December 2010, and demonstrates our ongoing commitment to offering families newfound hope.
Our Experience with MMC 1995-2025
3,090
Prenatal referrals
More than 1,741
Prenatal evaluations
478
Fetal MMC surgeries
641
Babies with MMC delivered in our Special Delivery Unit since 2008
Data on file with the Center for Fetal Diagnosis and Treatment. 9/1995-2/1/2025
Key Outcomes and Measures of Success
- CHOP fetal myelomeningocele surgery outcomes mirror those reported in the MOMS trial.
- CHOP’s rate of transfusion (1.5 percent) is lower than that of the MOMS trial (9 percent) at the time of cesarean delivery due to the continuity of care and experience of the delivery team members.
- Rates of preterm labor and membrane separation were similar between the CHOP cohort and the MOMS trial.
- At CHOP, more than 50 percent of babies that undergo fetal surgery deliver at or after 35 weeks, similar to the MOMS trial gestational age at delivery.
- CHOP had a lower rate of PPROM (32.3 percent) compared to the MOMS trial cohort of 46.2 percent.
- On neonatal MRI, hindbrain herniation was reversed in more than 90 percent of our fetal spina bifida surgery patients.
- There were no CSF leaks from the fetal MMC surgery. The average birth weight was comparable to that of the MOMS trial.
- The rate of hydrocephalus therapy with a shunt or endoscopic third ventriculostomy (ETV) procedure at 12 months is 22 percent.
- A follow-up program is in place for improving long-term spina bifida outcomes.
Patient Characteristics and Delivery Outcomes
Patient Characteristics at Fetal Surgery
| Characteristic | CHOP n=100 | MOMS Trial n=78 |
|---|---|---|
| Maternal age, years | 29.7 +/- 4.5 | 29.3 +/- 5.3 |
| Gestational age, weeks | 23.3 +/- 0.8 | 24.0 |
| Body mass index (BMI), Kg/m2 | 26.3 +/- 4.4 | 26.2 +/- 3.7 |
Delivery Outcomes in fMMC Patients
| CHOP | MOMS Trial | |
|---|---|---|
| Delivery at CHOP | 89/98* 90.8% | |
| Transfusion | 3/89 3.4% | 7/78 9% |
| Postoperative length of stay | 3.1 days (2-4) | NR |
| Hysterotomy at delivery (intact) | 44/87 50.6% | 49/76 64% |
| Hysterotomy at delivery (thin) | 36/87 41.4% | 19/76 25% |
| Membrane separation | 22/96 22.9% | 20/78 25.6% |
| Preterm premature rupture of membranes (PPROM) | 31/96 32.3% | 36/78 46.2% |
| Preterm labor (PTL) | 36/96 37.5% | 30/78 38.5% |
*At time of publication, two had not delivered.
NR = Not Reported
Neonatal Outcomes Associated with fMMC
Hindbrain Herniation on MRI
| CHOP | MOMS Trial | |
|---|---|---|
| No evidence | 59/83 71.1% | NR |
| Yes | 13/83 15.7% | NR |
| Mild/Minimal | 7/83 8.4% | NR |
| Not imaged | 4/83 4.8% | NR |
Perinatal Death
| CHOP | MOMS Trial | |
|---|---|---|
| Intrauterine fetal demise (IUFD) | 2 | 1 |
| Neonatal demise (NND)* | 4 | 1 |
*In neonatal demise (NND) cases, preterm premature rupture of membranes (PPROM) or preterm labor (PTL) occurred within two weeks of fMMC repair.
Additional Outcomes
| CHOP | MOMS Trial | |
|---|---|---|
| Birth weight | 2415.5 g (501-3636) | 2383 +/- 688 |
| Dehiscence at repair site | 3/83 3.6% | 10/77 13% |
| Shunt prior to discharge | 2/83 2.4% | NR |
| Respiratory distress syndrome* | 43/83 51.8% | 16/77 21% |
| Apnea | 48/83 57.8% | 28/77 36% |
| Caffeine therapy | 43/83 51.8% | NR |
| Length of stay | 24.5 days (3-133) | NR |
| Foot deformity | 32/83 38.6% | 39/78 50% |
*The results of respiratory distress syndrome prompted the clinical team to create a clinical care pathway for fMMC neonates in order to monitor them closely for RDS.
NR = Not Reported
References
Adzick NS, Thom EA, Spong CY, Brock JW 3rd, Burrows PK, Johnson MP, Howell LJ, Farrell JA, Dabrowiak ME, Sutton LN, Gupta N, Tulipan NB, D’Alton ME, Farmer DL; MOMS Investigators. A Randomized Trial of Prenatal Versus Postnatal Repair of Myelomeningocele. N Engl J Med. 2011 Mar;364(11):993–1004.
Moldenhauer JS, Soni S, Rintoul NE, Spinner SS, Khalek N, Martinez-Poyer J, Flake AW, Hedrick HL, Peranteau WH, Rendon N, Koh J, Howell LJ, Heuer GG, Sutton LN, Johnson MP, Adzick NS. Fetal Myelomeningocele Repair: The Post-MOMS Experience at the Children’s Hospital of Philadelphia. Fetal Diagn Ther. 2014 Aug 15. [Epub ahead of print]