Epidemiology and outcome of congenital diaphragmatic hernia: a 9-year experience.

The aim of this study was to report the birth prevalence and short-term outcome of congenital diaphragmatic hernia (CDH) in a large geographically defined population, and to assess the feasibility of performing a randomised control trial (RCT) in this population. Data were collected on all cases of CDH reported to the East Midlands and South Yorkshire Congenital Anomalies Register between 1997 and 2005. A total of 194 cases of CDH were identified from 547,025 births; a birth prevalence of 3.5/10,000. Overall 1-year survival was 42%. In total, 69% of cases resulted in a live birth, of these 61% survived to 1 year; 73% were diagnosed antenatally and 22% postnatally, with 1-year survivals 30% and 71%, respectively. A total of 54% were isolated cases and 46% associated with another anomaly, with more live births (80% vs. 56%) and better 1-year survival (62% vs. 19%) with isolated CDH. Overall, only 83 babies were born alive with an isolated CDH: the only group suitable for inclusion in a RCT. In conclusion, given the small numbers of live isolated CDH cases it is impossible that any network alone would be able to perform a valid RCT of treatments, highlighting the need for collaborative international trials to address this complex condition.