MOMS trial shows great benefit for fetal surgery in myelomeningocele

The results of the  landmark major multi-center randomized clinical trial "Management of Myelomeningocele Study (MOMS)" report on fetal surgery for spina bifida has been published in the 9 February issue of the New England Journal of Medicine, NEJM. The results indicate that prenatal surgery for spina bifida has greatly improved benefits over postnatal repair, by reducing the need for shunting and improving motor outcomes.

The randomized clinical trial is the first that systematically evaluated the best treatment for myelomeningocele. The eight-year trial was stopped early since the results suggested that fetal surgery greatly reduced the need for postnatal intervention. The early intervention in utero also resulted in improved motor development.The early success of the trial has been cause for celebration at UCSF, who carried out the first human fetal surgery some thirty years ago.The surgical procedures evaluated in this trial, known as the Management of Myelomeningocele Study (MOMS), were developed at UCSF's Fetal Treatment Center, under the direction of Michael Harrison, UCSF professor emeritus of clinical surgery, pediatrics, obstetrics and gynecology.Harrison, often referred to as the "Father of Fetal Surgery", performed the world's first open fetal surgery 30 years ago at UCSF, and the institution has also trained most of the current leaders in the field.

The study originally planned to enroll 200 pregnant women carrying a child with myelomeningocele, but was stopped early, with only 183 participants enrolled, because of the significant benefits shown in the children who underwent fetal surgery. The pregnant women were randomly assigned to one of two groups: a prenatal surgery group and a postnatal surgery group. The prenatal group underwent surgery to close the spinal defect in the fetus before the 26th week of pregnancy. The babies born in the postnatal group had the standard surgery in the usual time frame. The children underwent independent evaluation at 12 months and 30 months. At 12 months of age only 39.7% of children in the prenatal surgery group needed csf shunt surgery compared to 82.5% in the postnatal surgery group. Standardized motor and cognitive outcome assessments performed at 30 months saw the prenatal surgery group scoring significantly higher than the postnatal surgery group. 41.9% of the children in the fetal surgery group were able to walk unaided compared to only 20.9% in the postnatal group.

It should however be noted that there are risks to the mother and fetus associated with early intervention and this option might not be suitable in all cases.

A Randomized Trial of Prenatal versus Postnatal Repair of Myelomeningocele. N. Scott Adzick, Elizabeth A. Thom, Catherine Y. Spong, John W. Brock, Pamela K. Burrows, Mark P. Johnson, Lori J. Howell, Jody A. Farrell, Mary E. Dabrowiak, Leslie N. Sutton, Nalin Gupta, Noel B. Tulipan, Mary E. D'Alton, Diana L. Farmer (2011)
New England Journal of Medicine p. 110209140307019
http://www.nejm.org/doi/abs/10.1056/NEJMoa1014379