[Extrauterine pregnancy: sonographic criteria and their clinical value]

The most common criteria for the ultrasonic diagnosis of ectopic pregnancy are: 1. An enlarged uterus without a gestational sac, 2. A progesterone-stimulated endometrium (internal uterine echos), 3. Cul-de-sac fluid (blood) and 4. An adnexal tumour. To assess the clinical usefulness of the described criteria in a prospective study, ultrasonography was performed preoperatively in 25 patients with ectopic pregnancy. The ultrasonograms were coded for uterine size, intrauterine echoes, adnexal mass, and cul-de-sac fluid. Of 25 ectopic pregnancies, a correct positive ultrasonic diagnosis was made in 80%, while a false negative diagnosis was made in 20%. In most cases an adnexal mass could be identified (68%), whereas cul-de-sac fluid and an uterine enlargement without gestational sac was seen only in one-half of the patients. Internal uterine echoes could be found in only 36% of the patients. An ectopic gestational sac with viable foetus was seen in one case only. Due to the variability of ectopic pregnancy, no pathognomonic features can be defined. For this reason, ultrasonography cannot be considered an absolutely reliable method for the diagnosis of ectopic pregnancy.