Application of ultrasound in the diagnosis of heterotopic pregnancy--a review of the literature.

The world literature between 1979 and 1984 has been reviewed in regard to the use of ultrasound in the diagnosis of heterotopic pregnancy. Although ultrasonography is helpful in detecting the intrauterine pregnancy, it is far less accurate for diagnosing the associated ectopic pregnancy. A clear-cut ultrasonographic diagnosis prior to surgical intervention could be made in only 4 of 29 cases (14%), where viable intra- and extrauterine fetuses were observed.