Disappearance of human chorionic gonadotropin following removal of the fetus and placenta left in situ in a case of advanced abdominal pregnancy.

In a case of abdominal pregnancy, human chorionic gonadotropin (hCG) was determined twice during the first trimester and serially after removal of the fetus and placenta left in situ. From the 5th to the 7th week of gestation, the hCG values increased, from 5980 to 10000 U/l. After operation the hCG level decreased to 197 U/l after 51 days and hCG was not detectable 72 days postoperatively.