IS THE HUMAN CHORIONIC-GONADOTROPIN SECRETED BY ECTOPIC TROPHOBLAST DIFFERENT FROM THAT IN NORMAL INTRAUTERINE PREGNANCIES

Objective: To determine whether different isoforms of hCG are secreted by trophoblast tissue from ectopic pregnancy (EP). Design: Retrospective study of surgically confirmed EPs compared with normal pregnancies. Setting: Teaching hospital in South Africa. Patients: One hundred patients with EPs and 120 patients with normal pregnancies. Main Outcome Measures: Isoforms of hCG were measured by specific immunoassays, lectin binding, and examination of disappearance rates of hCG after surgical clearance of EP. Results: There were no obvious differences between the two types of pregnancy apart from a lower binding of beta-subunit immunoactivity to ricin 120. No clinically useful diagnostic measures to distinguish hCG from normal and EPs were found. Conclusions: No obvious differences were found in the isoforms of hCG between the two types of pregnancy using these methods.