The outcome of antenatally diagnosed urological abnormalities.

Twenty-eight patients undergoing routine antenatal screening by ultrasound were found to have a fetus with a major urological abnormality. In addition, two babies suspected of having an enlarged bladder were found post-natally to be normal. Seven of the 28 pregnancies were terminated before 26 weeks' gestation as a result of the ultrasound findings and all these fetuses had lethal renal abnormalities. Of the remaining 21 babies, four died of renal failure following delivery. Fifteen of the 17 babies who are alive and well had an ultrasound scan before 24 weeks' gestation. Only one of these scans revealed the abnormality. In the remaining patients the abnormality was first detected after 28 weeks. No patient had surgery in utero. Our data suggest that renal abnormalities detected prior to 24 weeks' gestation are associated with severe renal impairment. It appears that the role of antenatal drainage procedures may be of limited value.