In cases of suspected ectopic pregnancy, which imaging test is typically performed next?

Transvaginal ultrasound is the preferred imaging test in cases of suspected ectopic pregnancy because it provides the highest sensitivity for detecting early gestational structures in the pelvis. This method allows for a closer view of the uterus and surrounding pelvic organs, facilitating the identification of any abnormal masses or fluid, such as the presence of an ectopic pregnancy in the fallopian tube or elsewhere. Additionally, transvaginal ultrasound can also help assess the endometrial lining and any signs of intrauterine pregnancy, thus informing further management decisions.

In contrast, while other imaging modalities like CT scans or MRIs can be used in certain situations, they are typically not first-line choices in the setting of suspected ectopic pregnancy due to the increased radiation exposure from a CT scan and the cost and complexity associated with MRI. Transabdominal ultrasound may also be utilized, but it is often less effective than transvaginal ultrasound in early pregnancy evaluation. Therefore, transvaginal ultrasound stands out as the most appropriate imaging test for this clinical scenario.