title: The shape of the endometrium evaluated with three-dimensional ultrasound: an additional predictor of extrauterine pregnancy.
abstract: The objective of this prospective follow-up study was to evaluate the potential utility of three-dimensional (3D) ultrasound to differentiate intrauterine from extrauterine gestations. Fifty-four pregnancies with a gestational age <10 weeks and with an intrauterine gestational sac <5 mm in diameter formed the study group. The configuration of the endometrium in the frontal plane of the uterus was correlated to eventual pregnancy outcome. After exclusion of three patients with a poor 3D-image quality the endometrial shape was asymmetrical with regard to the median longitudinal axis of the uterus in 84% of intrauterine pregnancies, whereas the endometrium showed a symmetry in the frontal plane in 90% of extrauterine pregnancies (P = 0.0000001). Intrauterine fluid accumulation may distort the uterine cavity, thus being responsible for false-positive as well as false-negative results. The evaluation of the endometrial shape in the frontal plane appears to be a useful additional means to distinguish intrauterine from extrauterine pregnancies, especially when a gestational sac is not clearly demonstrated with conventional ultrasound.
authors.affiliation: Department of Obstetrics and Gynaecology, University of Würzburg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Rempen
mesh_terms: D000022:Abortion, Spontaneous / Q000000981:diagnostic imaging; D000328:Adult; D001755:Blastocyst / Q000000981:diagnostic imaging; D001826:Body Fluids / Q000000981:diagnostic imaging; D006063:Chorionic Gonadotropin / Q000652:urine; D003656:Decidua / Q000000981:diagnostic imaging; D004717:Endometrium / Q000000981:diagnostic imaging*; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome; D011271:Pregnancy, Ectopic / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000652:urine; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000379:methods* / Q000706:statistics & numerical data; D014592:Uterine Hemorrhage / Q000000981:diagnostic imaging
chemical_list: D006063:Chorionic Gonadotropin