Anderson I H, Jones G R, Standen J R
J Can Assoc Radiol. 1983 Mar;34(1):29-31.
We examined 100 consecutive patients presenting for gestational assessment by ultrasonography for hydronephrosis. Hydronephrosis in these patients was assessed in respect of its incidence, degree, laterality, and its relation to stage of gestation. Hydronephrosis was found to be present in approximately half of our patients particularly in the second and third trimesters. Hydronephrosis was more prevalent on the right than on the left side. We believe that hydronephrosis of pregnancy is physiologic and that both mechanical and hormonal factors contribute to its occurrence.