Elevated hCG Concentration in a Patient after an Unsuccessful in vitro Fertilization

A patient had a positive serum human chorionic gonadotropin (hCG) 22 days after a failed in vitro fertilization (IVF). The result was confirmed by repeating the test using quantitative and qualitative assays after 48 hours, but the quantitative result did not double compared to the previous concentration. Heterophilic antibody interference was ruled out. The above results indicated true-positive hCG, but inconsistent with normal pregnancy. Medical history excluded hCG produced by pituitary gland, malignancy and exogenous hCG use. Ectopic pregnancy (EP) was suspected and methotrexate was initiated. Ultrasound showed periadnexal fluid suggesting separation phenomenon on the right adnexal EP and hCG was decreased one weeks after the treatment. Two weeks later, hCG became negative. The above data suggest that the elevated hCG was most likely due to EP following IVF.