Significant improvement in hydronephrosis with pyeloplasty prior to 3 months of age in patients with antenatal severe hydronephrosis.

Introduction: Pyeloplasty is the definitive management of ureteropelvic junction obstruction (UPJO). One of the challenging questions is when to perform pyeloplasty. We studied if improvement post-pyeloplasty in the first 3 months of life could show greater improvement in hydronephrosis than surgery at an older age.