'Congenital' hydronephrosis: limitations of diagnosis by fetal ultrasonography.

OBJECTIVE

To determine whether children presenting clinically with pelvi-ureteric junction obstruction had fetal hydronephrosis.

PATIENTS AND

METHODS

Forty-three children, born during or after 1985, presented clinically with pelvi-ureteric junction obstruction. Records of the maternal pregnancies were reviewed with reference to the findings of any fetal ultrasonography.

RESULTS

In 25 patients fetal ultrasonography was performed at or beyond 30 weeks' gestation (mean 33.2). None had significant fetal hydronephrosis.

CONCLUSION

Hydronephrosis due to pelvi-ureteric obstruction is not necessarily congenital and patients presenting clinically may differ inherently from those detected fetally.