Congenital diaphragmatic herniation: antenatal detection and outcome

201 fetuses and babies with a congenital diaphragmatic herniation or eventr ation (referred to collectively as CDH) were notified to the Northern Regio n Congenital Abnormality Survey (NorCAS) in the 13-year period from 1985 to 1997, an incidence of 0.25 per 1000 births. The I-year survival of all pre gnancies associated with CDH was 37%. The 1-year survival of livebirths was 50%. Antenatal scan detected the diaphragmatic defect or associated struct ural abnormality in 50%. Another major structural abnormality was present i n 62 (31%); one of these babies survived and 26 pregnancies were terminated . This group contained four of the six antepartum stillbirths, all three in trapartum stillbirths and four of the five spontaneous miscarriages. Non-is olated CDH occurred in association with Fryns (5), Goldenhar (1) and de Lan ge (1) syndromes, and in 16 of 17 with a chromosome anomaly. 53% of the 139 fetuses with isolated CDH survived to 1 year of age, and 59% of the 124 li veborn survived. Of 37 fetuses with isolated CDH detected before 25 weeks g estation, 12 pregnancies were terminated. There were 11 survivors among the 25 continuing pregnancies (44%). The overall survival of babies with CDH i s very poor but, when a defect is identified by ultrasound before 25 weeks gestation, chromosome analysis and a careful ultrasound scan may suggest wh ich fetuses have an isolated diaphragmatic abnormality and a greater chance of survival.