• Ectopic pregnancy;
  • human placental lactogen;
  • pregnancy immunology

PROBLEM: To establish a rapid test differentiating ectopic from failed intrauterine gestation, using placental lactogen (PL) as a marker for placental cells. METHOD OF STUDY: Sixteen Swiss Webster mice had synchronized ovulation and were mated. Eight mice were unmated controls. Study and control mice were sacrificed at 5, 7, 9, and 11 days gestation. Uterine sections were tested for PL by immunofluorescent antibody assay, enzyme-linked immunosorbent assay, and dot blot analysis. Human endometrial samples from a missed abortion and a nonpregnant woman were also tested. RESULTS: Placental lactogen was detectable only in pregnant uterine samples (placental cells only) by all assays and was absent in the endometial glandular cells of nonpregnant uterine samples. CONCLUSION: Three methods detected placental lactogen in the pregnant mouse and human tissue. This is the first step towards developing a reliable clinical test for human endometrial samples from early pregnancy to differentiate early abortion from ectopic pregnancy.