Maternal hydronephrosis in pregnant women without ureteral stones and characteristics of symptomatic cases who need treatment: A single-center prospective study with 1026 pregnant women

Purpose: The aim of this study is to determine the proportion of maternal hydronephrosis and symptomatic cases requiring treatment in pregnant women without ureteral stones and the characteristics of these cases. Materials and methods: Between February 2018 and April 2019, all pregnant women followed for pregnancy in obstetrics and outpatient policlinic were evaluated prospectively. Maternal hydronephrosis rate, degree of hydronephrosis and side, symptomatic hydronephrosis rate, maximum renal anteroposterior diameter of renal pelvis and visual analogue scale were detected. Symptomatic patients were treated conservatively or surgically. Findings in both treatment groups were analyzed by t-test or Chi-squared test. Pearson or Spermean's tests were used for correlation analyzes. Results: A total of 1026 pregnant women aged 18-45 (27.7 +/- 5.2 years) were followed prospectively. The rate of maternal hydronephrosis was 28.7% and the rate of symptomatic hydronephrosis was 4.7%. Of the patients with symptomatic hydronephrosis, 73.4% (3.5% of total) were treated conservatively and 26.5% (1.3% of total) were treated surgically. There was a positive correlation between hydronephrosis and gestational week (p < 0.001), visual analogue scale (p < 0.001) and hematuria (p < 0.05). There was a negative correlation between hydronephrosis and maternal age (p < 0.05) and number of pregnancies (p < 0,001). The anteroposterior diameter of renal pelvis (p < 0.001), visual analogue scale (p < 0.05) and fetal body weight values (p < 0.0.5) on the right side were higher in the surgical treatment group than the conservative group. Conclusions: The majority of cases with maternal hydronephrosis in pregnant women without ureteral stones are asymptomatic. Most symptomatic cases can also be treated conservatively. In cases requiring surgical treatment (1.3%), fetal body weight, visual analogue scale and anteroposterior renal pelvis diameter are higher.