During a transabdominal ultrasound, which structure is typically evaluated first?

• A. Uterus
• B. Ovaries
• C. Gestational sac
• D. Bladder

Answer: (C)

In a transabdominal ultrasound, the bladder is usually evaluated first because it serves as an acoustic window for imaging pelvic structures. A full bladder distends the urinary bladder, which elevates the uterus and surrounding structures, providing a clearer view. This positioning allows sonographers to easily visualize the uterus and ovaries in relation to the bladder, ensuring that any assessments made thereafter are more accurate.

Evaluating the gestational sac first could lead to difficulties in visualization if the bladder is not adequately filled, as it may compress or obscure the anatomical structures required for a comprehensive examination. Therefore, starting with the bladder enhances the quality of the ultrasound images and facilitates better assessment of other pelvic organs subsequently.