Human chorionic gonadotropin (hCG, total hCG, hCG, Total hCG, Total beta hCG) hormone (HCG 2000IU) produced by the placenta during pregnancy, the human chorionic gonadotropin is a glycoprotein and consists of two alpha and beta subunits. Alpha subunits are homologous to those of luteinizing, follicle-stimulating and thyrotropic hormones, and beta-subunits differ and provide biological and immunological specificity.
The beta subunits of hCG and beta subunits of LH have several common peptide sequences; however, the structures of the carboxyl end are individual. After the fertilized egg is implanted in the uterine wall, trophoblasts of the placenta begin to synthesize hCG. The active secretion of hCG supports the corpus luteum, which remains functionally active throughout the entire gestation period, and produces large concentrations of progesterone, which are physiologically impossible in a non-pregnant organism. One week after fertilization, the analysis of hCG during pregnancy (normal course) can show a concentration of 50 IU / l in a blood analysis for hCG. During the first six weeks, if you give blood for HCG, you can see the dynamics, because the level doubles every 1.5–3 days and continues to increase until the beginning of the second trimester, after which during the remaining gestation period it gradually decreases to lower values. The concentration of hCG after childbirth in the blood test for hCG constitutes hCG is an excellent marker that helps to quickly determine pregnancy.
In healthy non-pregnant women, the concentration of the hormone in the blood test for hCG is from the sensitivity of the method (blood for hCG) allows you to diagnose pregnancy on the second day after the delay of menstruation, but due to individual differences in the rate of its synthesis, it is better to donate blood for hCG and conduct research Not earlier than 3 – 5-day delay in order to avoid false-negative results.