Prognosis in fetal diaphragmatic hernia.

The reported mortality for prenatally detected congenital diaphragmatic hernia is high. Polyhydramnios and presentation in early pregnancy have been suggested as high-risk factors adversely affecting outcome. We retrospectively reviewed 55 cases of congenital diaphragmatic hernia diagnosed prenatally in our unit. There was an overall mortality of 73%. The mortality in cases with presentation before 25 weeks' gestation was 74%, if the cases resulting in termination of pregnancy are excluded, compared with a mortality of 60% in those seen after this gestational age. Underdevelopment of left-sided cardiac structures was found to be a helpful prognostic factor. We were unable to confirm the predictive nature of hydramnios. Associated chromosomal anomalies were found in two fetuses and major congenital heart disease in nine. Although diagnosis before 25 weeks' gestation is associated with a higher mortality than in cases detected later, it is not universally fatal. If congenital heart disease and chromosomal anomalies are excluded and there is little or no evidence of left heart underdevelopment, the odds for survival will improve. This should be taken into account when the management of these cases is planned.