Home / News

What is HCG

HCG (human chorionic gonadotropin)-human chorionic gonadotropin is a glycoprotein hormone secreted by the trophoblast cells of the placenta. It is composed of two peptide chains α and β. It is the most commonly used "pregnancy test" hormone. It is often used to judge whether or not you are pregnant. Medical HCG is a white freeze-dried block or powder.


What is the role of HCG

1.With the functions of FSH and LH, it can maintain the life of the menstrual corpus luteum and increase the menstrual corpus luteum to become pregnant corpus corpus;

2.Promote the conversion of androgen aromatization into estrogen, while stimulating the formation of progesterone;

3.Inhibit the stimulating effect of plant lectins on lymphocytes. HCG can be adsorbed on the surface of trophoblast cells to prevent embryonic trophoblast cells from being attacked by maternal lymphocytes;

4.LH-like function. Before the fetal pituitary secretes LH, it stimulates the fetal testes to secrete testosterone to promote male sexual differentiation; it can also promote gonadal development, stimulate the vitality of testicular stromal cells for men, and increase the secretion of male hormones (testosterone). It is of great significance to the treatment of male patients with combined pituitary gland defects, not only can promote the development of the gonadal glands and the secretion of male hormones, but also promote the development of secondary sexual characteristics;

5.It can bind to the TSH receptor of maternal thyroid cells to stimulate thyroid activity.


At the same time, the numerical change of HCG also plays an important indicator role

1.Distinguish between normal and abnormal pregnancy: According to changes in normal HCG concentration, if the first HCG is within the normal range, 79% of people can be pregnant at full term, and if the first HCG is lower than normal, 92% of the pregnancy will fail. In particular, ectopic pregnancy is mostly due to insufficient blood supply at the implantation site, leading to poor growth of trophoblast cells, less HCG secretion, and lower than normal levels.

2.Diagnosis and treatment of miscarriage: incomplete miscarriage, there is still placental tissue remaining in the uterus, HCG is characterized as positive, HCG can be negative in complete miscarriage or stillbirth, if HCG is below 2500IU/L and gradually declines, miscarriage or stillbirth is possible; when it drops to 600IU/L, miscarriage is inevitable. If the HCG in the blood continues to drop, it means that the abortion is invalid, otherwise, it indicates that the abortion is successful. On 4 days after delivery or 13 days after induced abortion, serum HCG should return to normal. If this situation is not met, the possibility of abnormality should be considered.

3.Malignant hydatidiform mole, choriocarcinoma, and male testicular teratoma: In this case, the HCG is abnormally elevated. After surgical treatment, if the treatment is effective, the HCG gradually decreases to the normal level; if the HCG does not decrease but rises or maintains a high value, it indicates that the treatment is invalid or recurrence.

4.Others: HCG tends to be high in pregnancy-induced hypertension; HCG is generally higher in multiple pregnancy than in single pregnancy.

5.In addition, HCG also plays an irreplaceable role in the screening of Down syndrome and the diagnosis and treatment of male testicular cancer and other diseases.


What should be paid attention to when doing hcg inspection

1.In general hospitals, β-HCG testing is used for cytotrophication and pregnancy diagnosis.

2.Generally, the hcg test will be divided into urine test and blood test. If you don't know which one to use will be better, you can consider doing both to ensure authenticity.

3.If it is for β-HCG test, the doctor usually recommends the blood HCG test as the standard, while the urine test is easily affected by other factors. For example, some hormones, such as LH hormone, can react with the test paper and will appear false positives, such as thyroid hormones will have an impact. And it is difficult to identify which false positive is, so the urine test has more interference than the blood β-HCG.

4.Blood HCG is negative, urine HCG shows positive, the first thing to consider is the false positive problem. First, it may be related to the degree of urine concentration. The longer the urine is stored, the more HCG will accumulate, which will be detected by the kit false positive. Second, it may be due to the abnormal increase in the secretion of β-HCG cleavage enzymes secreted by the trophoblastic macrophages during the very pregnancy, so that too many degradation products are secreted into the urine, leading to false positives.

5.Generally, urine HCG cannot objectively reflect the condition of the disease. At the same time, the activity of trophoblasts should be monitored to provide accurate basis for clinical diagnosis and treatment. The blood HCG measurement result should be the most accurate. You can consider testing twice, if the blood HCG is negative, then the urine is a false positive.