Fetal kidneys may be identified as early as which gestational age?

Fetal kidneys may be identified as early as which gestational age?

• A. 12 weeks
• B. 15 weeks
• C. 18 weeks
• D. 20 weeks

Answer: (B)

Fetal kidneys become visible on ultrasound when they have grown enough to be distinguished within the retroperitoneum. This typically happens by mid-second trimester, with the earliest reliable identification around 15 weeks of gestation. At 12 weeks the kidneys are usually too small and the imaging resolution or fetal position can make them difficult to identify, whereas by about 18–20 weeks the kidneys are routinely seen as part of the anatomy survey. So, the earliest gestational age you can expect to identify the kidneys confidently is around 15 weeks.

Fetal kidneys become visible on ultrasound when they have grown enough to be distinguished within the retroperitoneum. This typically happens by mid-second trimester, with the earliest reliable identification around 15 weeks of gestation. At 12 weeks the kidneys are usually too small and the imaging resolution or fetal position can make them difficult to identify, whereas by about 18–20 weeks the kidneys are routinely seen as part of the anatomy survey. So, the earliest gestational age you can expect to identify the kidneys confidently is around 15 weeks.