Korean J Obstet Gynecol.  2005 Sep;48(9):2211-2216.

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

• Lee DY
• Yoon HJ
• Kim KH
• Kim HM
• Choi JS
• Lee KW
• Han JS
• Shon JH
• Chae SW
• Kim SH

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.

Keyword

Tubal pregnancy; Beta-hCG; Trophoblast

MeSH Terms

Chorionic Gonadotropin*
Fallopian Tubes
Female
Gestational Age
Humans*
Immunoassay
Mucous Membrane
Pregnancy
Pregnancy, Tubal*
Serous Membrane
Trophoblasts*
Chorionic Gonadotropin