title: Early diagnosis of ectopic pregnancy using receiver-operator characteristic curves of serum progesterone concentrations.
abstract: The objective was to assess the usefulness of serum progesterone concentrations in the differentiation of intra-uterine (viable and non-viable) and extra-uterine pregnancies. Progesterone concentrations were prospectively measured at 4, 5 and 6 weeks gestation in 338 pregnancies which resulted in 242 viable births, 81 abortions and 15 ectopic pregnancies. Progesterone threshold analysis was performed using receiver-operator characteristic curves. The progesterone threshold value for ectopic pregnancy at 4 weeks was 5 ng/ml, at 5 weeks 10 ng/ml and at 6 weeks 20 ng/ml. A significant difference was observed between all intra-uterine versus ectopic pregnancies (P = 0.0005), but not between viable versus non-viable intra-uterine pregnancies (P = 0.37). The differences were most clearly defined at 4 weeks and decreased with increasing gestation. We conclude that serum progesterone and gestational age taken together can differentiate intra-uterine from extra-uterine pregnancies with a very high sensitivity and specificity at 4 weeks gestation, a time when ectopic pregnancies are not evident on ultrasound examination.
authors.affiliation: Immunology Center for Reproduction and Transplantation, Indianapolis, IN.
authors.forename: J J
authors.initials: JJ
authors.lastname: Stern
authors.forename: F
authors.initials: F
authors.lastname: Voss
authors.forename: C B
authors.initials: CB
authors.lastname: Coulam
mesh_terms: D000022:Abortion, Spontaneous / Q000097:blood; D005260:Female; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome; D011271:Pregnancy, Ectopic / Q000097:blood / Q000175:diagnosis*; D011374:Progesterone / Q000097:blood*; D011446:Prospective Studies
chemical_list: D011374:Progesterone