Reliability of urinary pregnancy tests in the diagnosis of ectopic pregnancy

Recently a new generation of urinary pregnancy tests with increased sensitivity and specificity for β-human chorionic gonadotropin (β-HCG) was introduced. The clinical sensitivity of seven of these tests was evaluated in patients with surgically proven ectopic pregnancy. Two enzyme-linked immunosorbent assays (Tandem Visual, Hybritech; Mod C1, Monoclonal Antibodies), with a sensitivity of 50 mIU of β-HCG, were positive in 90% of ectopic pregnancies. The three-tube tests (Sensitex, Roch; UCG Beta Stat, Wampole; β-Neocept, Organon), with a sensitivity of 150-250 mIU of β-HCG, were positive in 81-85% of ectopic pregnancies. Two slide tests (UCG Beta Slide, Wampole, and Sensislide, Roche), with a sensitivity of 500-800 mIU of β-HCG, were positive in 51-61% of ectopic pregnancies. Both the immunosorbent assays and the tube tests were statistically more sensitive than the slide tests (P<.001). There was no statistically significant increase in sensitivity between the tube tests and the immunosorbent assays. The sensitivities of these tube tests in ectopic pregnancy are similar to those of tube tests from other manufacturers previously reported on.