Congenital anomalies: Impact of prenatal diagnosis on mode of delivery.

An important aspect of prenatal diagnosis is the avoidance of emergency caesarean delivery (CD) where the abnormality is considered lethal and the infant will not survive. A consecutive cohort of 211,163 women delivered of infants weighing 500 grams or more in three tertiary referral centers from 01/95 to 12/04, was analyzed for perinatal death attributed to congenital malformations. In the group that died in the neonatal period, the emergency CD rate was significantly lower where anomaly was detected versus undetected (17.5% versus 31%). Further, in contrast to undiagnosed anomalies, the indication for emergency CD was more often maternal in the diagnosed group (42% versus 19%, p=0.019). When a diagnosis of lethal congenital anomaly has been made in the prenatal period, the reduction in the emergency CD rate by almost half in this study supports a pivotal role for prenatal diagnosis in optimizing maternal care.