Reappraisal of the predictive value of the beta-human chorionic gonadotropin assay in an infertile population.
In order to assess the clinical usefulness of human chorionic gonadotropin (hCG) in monitoring early abortion, we studied prospectively 108 pregnant patients. Of these subjects, 70 carried their pregnancies to term and delivered uneventfully, while 38 patients went on to develop first-trimester bleeding. Blood samples were obtained every 1 to 2 weeks during the first trimester, and, when bleeding developed, at least twice 2 or 3 days apart. beta-hCG was measured by a specific double-antibody radioimmunoassay. In the group with normal pregnancies, first-trimester serum beta-hCG gradually rose to reach a peak concentration of 16,875 +/- 4825 (SD) mIU/ml at 10 to 12 weeks of gestation. In the group with abnormal pregnancies, prior to the onset of bleeding, the mean serum beta-hCG level was 4- to 5-fold below that of normal subjects at equivalent gestational age, although with significant overlap in the 95% confidence limit (2 SD). Furthermore, when bleeding occurred, the individual rate of predicting abortion was at best 75% with an unacceptable rate of false-negative and false-positive predictions.
D000022:Abortion, Spontaneous / Q000097:blood*; D000033:Abortion, Threatened / Q000097:blood; D000328:Adult; D006063:Chorionic Gonadotropin / Q000097:blood*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011261:Pregnancy Trimester, First
D006063:Chorionic Gonadotropin