The CDH Study Group and advances in the clinical care of the patient with congenital diaphragmatic hernia.

Congenital diaphragmatic hernia (CDH) occurs in 1 of every 2000 to 4000 births and accounts for 8% of all major congenital anomalies. Recurrence risk for a subsequent pregnancy is estimated at 2%. The mortality rate for CDH when diagnosed antenatally, varies with fetal age and with the presence or absence of hydramnios and degree of pulmonary hypoplasia. The prognosis has improved dramatically in recent years, primarily due to advances in neonatal and surgical interventions. Neonatal survival rates with an antenatal diagnosis now exceed 80% in some centers. Treatment for infants with CDH reflects other pediatric surgical problems in that a majority of the clinical research that shapes treatment is retrospective in nature. Because CDH is a relatively rare disease, using a compilation of cases, such as the CDH database provides, greatly aids our understanding of this disease process. Moreover, the application of a quality assessment scale provides the practitioner with a knowledge base to critically evaluate the published retrospective data.