What renal changes occur during pregnancy?

What renal changes occur during pregnancy?

• A. Hydroureter and hydronephrosis with renal volume increasing 30% and kidneys lengthening by 1 cm
• B. Kidney shrinkage
• C. No renal changes
• D. Only one kidney enlarges

Answer: (A)

In pregnancy, hormonal relaxation of smooth muscle plus the growing uterus pressing on the urinary tract lead to dilation of the ureters and renal pelvis. This causes hydroureter and hydronephrosis, a common finding, especially on the right, as the urinary tract accommodates increased flow and delayed clearance. At the same time, increased renal blood flow and glomerular filtration rate contribute to a rise in kidney size, with renal volume commonly increasing by about 30% and the kidneys appearing longer by around 1 cm. This combination—hydronephrosis/hydroureter with a measurable increase in renal size—fits what is observed in pregnant individuals. The other options don’t reflect these coordinated anatomic and functional changes during pregnancy.

In pregnancy, hormonal relaxation of smooth muscle plus the growing uterus pressing on the urinary tract lead to dilation of the ureters and renal pelvis. This causes hydroureter and hydronephrosis, a common finding, especially on the right, as the urinary tract accommodates increased flow and delayed clearance. At the same time, increased renal blood flow and glomerular filtration rate contribute to a rise in kidney size, with renal volume commonly increasing by about 30% and the kidneys appearing longer by around 1 cm. This combination—hydronephrosis/hydroureter with a measurable increase in renal size—fits what is observed in pregnant individuals. The other options don’t reflect these coordinated anatomic and functional changes during pregnancy.