Human chorionic gonadotropin in early normal and pathologic pregnancy. Discordant levels in peripheral maternal blood and blood from the uterine and abdominal cavities.

Human chorionic gonadotropin was assayed in 25 cases after first-trimester induced abortion, in 45 cases of spontaneous abortion in the first trimester, and in 27 cases of ectopic pregnancy. Blood was obtained from an antecubital vein and from the uterine cavity. In the cases of ectopic pregnancy blood was also obtained from the abdominal cavity. In the group of induced abortion the human chorionic gonadotropin levels in peripheral maternal blood did not differ significantly from the levels in the uterine cavity. In the groups of spontaneous abortion and ectopic pregnancy the human chorionic gonadotropin levels were significantly higher in blood from the uterine cavity and the abdominal cavity, respectively. In four cases (three with spontaneous abortion and one with an ectopic pregnancy) human chorionic gonadotropin was not detectable in peripheral maternal blood, while it was found in blood from the uterine and abdominal cavities.