Objectives: To describe the true incidence, prenatal detection rate and fetal outcome of congenital diaphragmatic hernia (CDH) in a systematically registered population over an 18-year period and to determine any change in trends over time.
Methods: This was a retrospective study of all cases of CDH registered in the Central-Eastern France Birth Defects Registry from 1986 to 2003. All fetuses and infants up to 1 year of age diagnosed with CDH were registered, including miscarriages later than 22 weeks of gestation, stillbirths and terminations of pregnancy (TOP). Routine prenatal screening consisted of three ultrasound examinations and there was no upper limit of gestational age for TOP.
Results: Five hundred and one cases of CDH were identified from a total of 1 835 022 live births (2.7 cases per 10 000 live births). The overall prenatal detection rate was 54%. There was a significant increase over time in the detection rate mainly for associated CDH and left-sided CDH (P < 0.0001), and in the proportion of neonates delivered in tertiary centers (P < 0.0001). The overall survival rate at discharge was 47% and this increased significantly over time for isolated CDH (P = 0.04), whereas it was lower and remained stable for associated CDH (P = 0.64). The TOP rate for isolated CDH did not vary significantly in contrast to that for associated CDH cases in which the TOP rate increased over time, progressively replacing the neonatal death rate (P = 0.01).
Conclusions: Over an 18-year period, this large population-based study demonstrated increasing prenatal detection rates for associated CDH and left-sided CDH and confirmed an increasing survival rate mainly for isolated CDH.