Objectives: This report is intended to summarize the current state of practice and research in maternal-fetal surgical procedures, which is the surgical repair of abnormalities in fetuses in the womb.
Data Sources: We searched MEDLINE from 1980 forward for studies of fetal surgical procedures for the following seven conditions: congenital diaphragmatic hernia, cardiac malformations, myelomeningocele, obstructive uropathy, sacrococcygeal teratoma, twin-twin transfusion syndrome, and thoracic lesions. We also searched the Internet for sources of current practice, current insurance coverage of fetal surgery, and ongoing research (including the clinicaltrials.gov and NIH (National Institutes of Health) Reporter databases). We spoke with experts in the field regarding their knowledge of practice sites, ongoing training programs, research in the field, and considerations for the future of maternal-fetal surgical procedures.
Review Methods: We abstracted data on operational definitions of fetal diagnoses, type of procedure, maternal inclusion criteria, training of providers, study design, country, setting, comparators used, followup, outcomes measured, and adverse events. We summarized these data quantitatively. We attempted to identify all potential sources of care for maternal-fetal surgical procedures in the United States, and to summarize the state of the field.
Results: One hundred sixteen studies captured for this review were case series. There were 3 randomized controlled studies (RCTs) and the rest (47) were cohorts. Seventy-four studies were conducted in the United States; 68 were in Europe, and the rest in other parts of the world. One RCT was published as this report was in press; the study’s findings add to the body of literature on maternal-fetal surgical procedures for myelomeningocele and are summarized in that section of the report. The most common outcomes measured across diagnoses were survival to birth, preterm birth, and neonatal death. Additional, longer term outcomes for infants were rare, but when reported included pulmonary and neurologic status as well as achievement of developmental milestones. Reports of maternal outcomes were exceedingly rare, and in particular, we note very few studies that addressed the issues of future reproductive function for the mother. There are few formal training programs and no system of accreditation or licensure.
Conclusions: While developing rapidly, research on fetal surgical procedures has not achieved the typical level of quality of studies and aggregate strength of the evidence used to reach definitive conclusions about care and policy. Overall momentum is toward more robust research and rigorous, more consistent documentation of outcomes over longer periods of time. Experts concurred in discussions as well as in the literature that they are eager to develop consensus measures as well as mechanisms to make implementation of common protocols and larger studies increasingly possible. Favorable signs include the substantive leadership of U.S. researchers across each of the topics considered. For each target condition, there are both fetal surgical centers and associated research enterprises engaged in the full spectrum of academic endeavor, from animal research and development of surgical interventions and refinements, to patient care, surgical training, bioethics forums, and reporting of results in the scientific literature.