What type of ultrasound is contraindicated for pregnant women with placenta previa?

The appropriate selection is an intravaginal ultrasound, which is contraindicated for pregnant women with placenta previa. This condition involves the placenta being positioned abnormally low in the uterus, potentially covering the cervix. Inserting a probe intravaginally poses a risk of triggering bleeding or causing complications, as the lower segment of the uterus is particularly vulnerable in these cases.

Other types of ultrasound, such as echocardiogram, abdominal ultrasound, and pelvic ultrasound, do not involve any invasive procedure that would increase the risk of bleeding associated with placenta previa. An abdominal ultrasound, in particular, is often preferred because it can provide necessary imaging without the risks that an intravaginal approach carries. Pelvic ultrasound could be risky as well, but in many practices, abdominal ultrasound has become the standard for evaluating conditions like placenta previa, minimizing risks while still providing adequate diagnostic information.