Is it accurate to test hcg in blood 10 days after sex?

You can check the hCG level in the blood ten days after having sex. The test at this time is relatively accurate. Generally speaking, if you are pregnant, you can check the hCG level in the blood one week later, because its value will increase at this time and can be detected. In addition, you can also use early pregnancy test paper to check about two weeks after having sex. If the test is done too early, it may not be detected.

What is the normal value of hCG?

The normal value of blood hCG is <10μg/L, and the normal value of β-hCG is <3.1μg/L. β-hCG is a part of hCG. Generally, the β-hCG radioimmunoassay value of a normal woman is less than 3.1. If it exceeds 5, the possibility of pregnancy can be considered. If it exceeds 10, pregnancy can be basically confirmed.

The absolute values ​​of serum hCG vary greatly at different stages of pregnancy and between pregnant women. They are not comparable with each other and can only be compared within themselves. During the first 3 months of pregnancy, hCG levels approximately double every 2.2±0.5 days.

hCG values ​​over time

Human chorionic gonadotropin enters the maternal blood after fertilization and proliferates rapidly until the 8th week of pregnancy, then slowly decreases in concentration until the 18th to 20th week, and then remains stable. Generally, a level of at least 2.5 MoM of intact human chorionic gonadotropin is associated with Down syndrome. However, the actual average level of complete human chorionic gonadotropin in the maternal blood of DS patients is only 1.3MoM, which cannot clearly identify DS patients. The human chorionic gonadotropin-related molecules used for DS examination are free b-hCG and high sugar hCG (H-hCG).

The levels of human chorionic gonadotropin-related molecules are also related to the sex of the fetus. The levels of human chorionic gonadotropin in baby girls are significantly higher than those in baby boys.

Complete human chorionic gonadotropin is produced entirely by the syncytiotrophoblast of the placental chorion. Human chorionic gonadotropin is produced by trophoblast transitional cells and syncytial cells. Human chorionic gonadotropin begins to be secreted 10-14 days after conception.

Function of hCG

1. It has the functions of FSH and LH, maintains the life of the menstrual corpus luteum, and enlarges the menstrual corpus luteum into the corpus luteum of pregnancy;

2. Promote the aromatization of androgens into estrogen and stimulate the formation of progesterone;

3. Inhibit the stimulation of plant lectins on lymphocytes. Human chorionic gonadotropin can be adsorbed on the surface of trophoblast cells to prevent embryonic trophoblast cells from being attacked by maternal lymphocytes;

4. It has LH-like function. Before the fetal pituitary gland secretes LH, it stimulates the fetal testicles to secrete testosterone to promote male sexual differentiation. It can also promote gonadal development, stimulate the activity of interstitial cells in the testicles in men, and increase the secretion of androgen (testosterone). It is of great significance for the treatment of male patients with combined pituitary deficiency. It can not only promote gonadal development 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 and stimulate thyroid activity.