Tatsuo Morita’s research while affiliated with Jichi Medical University and other places

... According to statistical analyses, neonatal hydronephrosis is the most common genitourinary disease in children. The stenosis of the junction of the fistula, posterior urethral valve, multiple cysts of the kidney, ureteral cyst, lower ureteral obstruction, vesicoureteral reflux and other causes lead to hydronephrosis in newborns (2)(3)(4). International neonatal urology association proposed that separation of the renal collecting system more than 5 mm before 24 weeks or more than 10 mm after 24 weeks was used as the standard for the diagnosis of neonatal hydronephrosis (5). At present, study on the diagnosis and pathological evolution of neonatal hydronephrosis is not complete and has great controversy (6). ...

Reference:

RBP and Alb in neonatal hydronephrosis and its association with IL-12 levels in pregnant women before delivery

... Then, how about the patient's course, both in the long and short term? As was previously suggested [2,3,5], some patients may remain "asymptomatic", depending on the rupture site, size, condition of the vessels around it, and, finally, the rupture's spontaneous closure (þ or e). ...

Reference:

Asymptomatic uterine rupture detected at cesarean section: Some different viewpoints