Ultrasound evaluation of abdominal pregnancy.

The ultrasound diagnosis of abdominal pregnancy continues to be difficult in spite of recent advances in ultrasound technology. The principal impediment is a low suspicion for the diagnosis because of its relatively asymptomatic nature and the lack of specificity of symptoms when present. In the early days of sonography when static B-mode scanning was used, a "gestalt" diagnosis was suggested, based on one's ability to have an overall perspective of the intrauterine contents. With conversion to exclusive real time imaging and the inherent limitation of the field of view, this "gestalt perception" is no longer possible. It is therefore necessary to reassess our criteria based on this change and determine those that remain reliable for diagnosis.