Human chorionic gonadotropin and invasion of trophoblast into the tubal wall in tubal pregnancy / 대한산부인과학회지

ABSTRACT

OBJECTIVE: To evaluate the relationship between gestational age, tubal ultrasonographic diameter, and serum beta-hCG levels and different stages of trophoblastic infiltration of the tubal wall in tubal pregnancy. METHODS: The 45 cases of fallopian tube containing tubal pregnancy were reviewed. Gestational age, diameter of the tubal mass, and beta-hCG level on the day of surgery were calculated by transvaginal sonography and immunoassay respectively. The tubal pregnancy was classified according to the depth of trophoblastic infiltration: trophoblast limited to the tubal mucosa (stage I), extension to the tubal muscularis (stage II), or complete tubal wall infiltration up to the serosa discontinued by trophoblastic cells (stage III). RESULTS: 14 patients (31.1%) had stage I tubal infiltration, 10 patients (22.2%) had stage II infiltration, 21 patients (46.7%) had stage III infiltration. There was no relationship between gestational age, tubal diameter and stage, but there was a predictable correlation between beta-hCG and the depth of trophoblastic invasion. The median beta-hCG level was 1,332.1 mIU/mL (range, 215-2,995 mIU/mL) for patients with stage I infiltration, 9,548.0 mIU/mL (range, 569-43,989 mIU/mL) for stage II infiltration, and 23,087.9 mIU/mL (range, 1,373-98,000 mIU/mL) for stage III infiltration. Cut off level of beta-hCG for each stage were 1,996.5 mIU/mL (stage I vs II, III) and 5,665 mIU/mL (stage I, II vs III) respectively. CONCLUSION: These findings may explain why beta-hCG is a important predicting factor for invasion of trophoblast in tubal pregnancy.