HCG (human chorionic gonadotropin) is a glycoprotein hormone secreted by placental trophoblast cells.
After implantation, in order to settle firmly in the uterus, the fertilized egg will stretch out many small tentacles to grasp the inner wall of the uterus. These small antennae are human villi, and HCG is a hormone secreted by human villi, called human chorionic gonadotropin (HCG).
HCG, the most commonly used "pregnancy test" hormone, is often used to judge whether you are pregnant, such as early pregnancy test paper and pregnancy test stick.
HCG can stimulate the corpus luteum to change from menstrual corpus luteum to pregnant corpus luteum, promote the continuous secretion of estrogen and progesterone, maintain the morphology of endometrium, promote the formation of decidua of uterus, and make placenta grow and mature, which is very important for maintaining pregnancy.
Second, what is the role of HCG?
1, which has the effects of FSH and LH, maintains the life of menstrual corpus luteum and expands it into pregnant corpus luteum;
2. Promote the aromatization of androgens into estrogens and stimulate the formation of progesterone at the same time;
3. Inhibit the stimulating effect of plant lectin 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, which stimulates fetal testis to secrete testosterone to promote male sexual differentiation before fetal pituitary secretes LH; It can also promote gonadal development, stimulate the vitality of leydig cells in men, and increase the secretion of androgen (testosterone). It is of great significance for the treatment of male patients with premature pituitary closure, which can not only promote gonad development and androgen secretion, but also promote the development of secondary sexual characteristics.
5. It can bind with TSH receptor of maternal thyroid cells and stimulate thyroid activity.
Third, at the same time, the numerical change of HCG also plays an important indicator role:
1. Distinguish normal pregnancy from abnormal pregnancy: According to the change of normal HCG concentration, if the first HCG is within the normal range, 79% of people can have a full-term pregnancy, and if the first HCG is lower than normal, 92% of the pregnancies will fail. Especially for ectopic pregnancy, most of them are due to insufficient blood supply at the implantation site, which leads to poor growth of trophoblast cells and less HCG secretion, which is lower than the normal level.
2. Diagnosis and treatment of abortion: incomplete abortion, placental tissue remaining in the uterus, HCG qualitative positive, complete abortion or stillbirth when HCG can be negative, such as HCG below 2500IU/L, and gradually decreased, there is the possibility of abortion or stillbirth; When it drops to 600IU/L, abortion is inevitable. If HCG in the blood continues to drop, it means that the abortion is invalid, otherwise it means that the abortion is successful.
Serum HCG should return to normal 4 days after delivery or 13 days after induced abortion. If this is not the case, we should consider the possibility of abnormality.
3. Malignant hydatidiform mole, choriocarcinoma and male testicular teratoma: In this case, HCG is abnormally elevated. After surgical treatment, if the treatment is effective, HCG will gradually drop to normal level; If HCG does not decrease, but increases or maintains a high value, it means that the treatment is ineffective or recurs.
4. Others: Pregnancy-induced hypertension is often high in HCG; HCG in multiple pregnancies is generally higher than that in singleton pregnancies.
5. In addition, HCG plays an irreplaceable role in the screening of Down syndrome and the diagnosis and treatment of testicular cancer in men.
Four, the classification of HCG (type, inspection time; Correct rate):
HCG can be divided into blood HCG and urine HCG.
After HCG is secreted, it first enters the blood circulation and then enters the urine. It can be used to test whether you are pregnant or not. Blood HCG needs to go to the hospital for examination. The result is more accurate, the error is small, the accuracy rate is 99%, and it can be detected in advance. Urine HCG is a self-detection method with ovulation test paper or pregnancy test stick, and the accuracy is between 50% and 75%.
HCG is secreted by placental trophoblast cells and slowly secreted after fertilization, but it needs to reach a certain concentration to be detected.
Generally, it takes at least 1 1 to 14 days after sexual intercourse to detect HCG in urine, and it may be earlier through blood HCG detection, which can be reflected in a week or so.
5. What should I pay attention to when checking HCG?
Blood HCG test does not require fasting. Blood HCG detection can determine whether a woman is pregnant by measuring the HCG value in her blood.
As for HCG urine test, urine can be taken at any time of the day, but the first urine in the morning is the most accurate, and the urine will be diluted after drinking water. So it is best to be on an empty stomach.
Six, the change law of HCG value:
The level of HCG in serum and urine can increase rapidly from/kloc-0 to ~ 2.5 weeks of pregnancy, reaching the peak at 8 weeks of pregnancy, falling to the middle level at 4 months of pregnancy and maintaining it until the end of pregnancy.
When you are not pregnant, there should be no HCG in your body. blood test
After embryo implantation, HCG in maternal blood increased exponentially, reaching the peak in the eighth week of pregnancy, and then slowly maintained at 12 weeks. Before 42 days of pregnancy, B-ultrasound can't confirm whether you are pregnant, but it can confirm HCG. After 12 weeks, HCG in maternal blood decreased rapidly until 18 ~ 20 weeks later. By the middle and late pregnancy, the HCG concentration was only10% of the peak; Disappeared within 2 weeks after delivery.
If the rising speed is slow for two consecutive times, it indicates that ectopic pregnancy or embryo development is abnormally slow. For example, 10 today, 15 the day after tomorrow, and 17 two days later. This HCG value is definitely abnormal, and the success rate of miscarriage protection is extremely low. If the HCG value continues to drop significantly, even if the fetal heart is detected by B-ultrasound, it is best to curettage, indicating that the fetus is actually brain dead.
If HCG rises rapidly, it means that hydatidiform mole is possible and must be closely monitored. Of course, it could be twins.
7. What are the normal reference values of two types of HCG after pregnancy?
1, blood HCG:
Normal value of HCG in blood
Non-pregnant women; (8-32)× 104IU/L (morning urine HCG level is the highest, close to serum level).
Note: the absolute value of serum HCG varies greatly between different stages of pregnancy and pregnant women, that is, people are different and can only compare themselves.
However, it should be pointed out that urine HCG sometimes appears false positive. There are many non-pregnancy factors that can lead to false positive test results, hematuria, ovarian tumors, taking some fertility drugs and so on. And may be stimulated by other hormones. For example, LH hormone sometimes reacts with test paper, and thyroid hormone may also affect it. Therefore, if you only use urine HCG semi-quantitative test paper to detect whether you are pregnant, you can't hammer it out completely. It is still based on the test results of blood HCG.
Eight, ectopic pregnancy and HCG
Usually pregnant for 5-6 weeks, you can check whether it is ectopic pregnancy by B-ultrasound.
In the early pregnancy, the level of HCG increased once every (2.2 0.5) days. The doubling time of HCG in normal early intrauterine pregnancy is 1.4-2.2 days, and that in abnormal pregnancy (ectopic pregnancy, abortion) is 3-8 days.
Under normal circumstances, after pregnancy, if the amount of β-HCG increases by more than 66% every two days, it can be diagnosed as intrauterine pregnancy; If the increase is less than 66%, it can be considered as ectopic pregnancy or intrauterine pregnancy dysplasia. Generally speaking, the positive predictive value of ectopic pregnancy excluding normal increase of HCG is about 95%.
Comparing the ultrasound results with the concentration of H CG, ectopic pregnancy can also be estimated. When HCG reaches 65,438+0,000 U/L, intrauterine pregnancy sac can be identified by transvaginal ultrasound, and when HCG reaches 6500 U/L, intrauterine pregnancy sac can be identified by transabdominal ultrasound. If not, ectopic pregnancy should be suspected.
Patients suspected of having ectopic pregnancy should continuously measure blood HCG. Abnormal pregnancy should be considered if the increase of blood HCG is less than 50% every 48 hours.
The HCG level of 85% ectopic pregnancy patients is lower than that of intrauterine pregnancy patients of the same pregnancy age. The blood HCG level of 2.5% normal intrauterine pregnancy is lower than the normal limit of 95%. At all stages of spontaneous abortion, the level of HCG in blood may also be low. The blood HCG levels of the three groups overlap.
Nine, small science-early symptoms of ectopic pregnancy
1, menopause. Before tubal pregnancy abortion or rupture, the symptoms and signs are not obvious, except for short-term menopause and pregnancy, sometimes there is pain in one lower abdomen. The fallopian tubes were normal or swollen at the time of examination.
2, abdominal pain. Abdominal pain, feeling of defecation, sometimes severe pain, accompanied by cold sweat dripping wet. When ruptured, the patient suddenly felt a tearing pain in one lower abdomen, often accompanied by nausea and vomiting.
3. Other symptoms. The symptoms of ectopic pregnancy are often atypical, and some patients will also have symptoms such as nausea, vomiting, frequent urination, urgency, pale face and decreased blood pressure.
4, vaginal bleeding. In early pregnancy, women may have a small amount of vaginal bleeding and bloody leucorrhea.
5, syncope and shock. Acute abdominal bleeding can cause hypovolemia and severe abdominal pain, ranging from syncope to shock.
X. What is the reason for the low HCG value during pregnancy?
1, miscalculation of pregnancy date: in the early pregnancy, if the blood HCG value is low, it may be due to miscalculation of the last menstruation.
Ectopic pregnancy: the blood HCG value is low, so check again the next day. If it is not doubled, you need to go to the hospital for B-ultrasound in 45 days to determine whether it is intrauterine pregnancy.
2, embryonic development retardation: it may also be caused by embryonic development retardation. If there is no bleeding, you should go to the hospital for fetal protection treatment in time. If there is no problem with the development of the embryo itself, after effective treatment, HCG will double.
Eleven, HCG is low, do you want to take HCG injection to protect the fetus?
Generally speaking, it is not recommended to inject HCG at the beginning, because after injecting HCG, you will not see HCG double. However, if there is habitual abortion or signs of abortion, HCG can be considered.
Suggestion: It is best to check the HCG and progesterone every other day before deciding whether to fight.
12. Does it hurt to get an HCG injection?
If HCG is mixed with 10ML physiological saline, spanking is painless; But if you use a few milliliters of water for injection, it will really kill you.
Thirteen, what is the reason for the high HCG value during pregnancy?
It may be the following reasons:
1, it may be that the time of the last menstruation was miscalculated, which led to the discrepancy between the actual gestational age and the expected gestational age.
Solution: Recalculate the last menstruation and the actual gestational age, and then compare it with the normal reference value for estimation.
2. It may be twins or multiple births, because the number of multiple births is higher than that of singletons.
If it is confirmed by the doctor that it is the above two situations, then the expectant mother need not worry.
3, it may be an abnormal pregnancy-hydatidiform mole, and the blood HCG value is usually higher than the normal pregnancy value of the corresponding gestational age.
Solution: If hydatidiform mole is diagnosed, it needs to be cleaned up at the hospital immediately, otherwise there will be serious consequences such as uterine perforation and infection.
4. On Down's screening list, the median reference range of β-HCG is 0-2.5. If it is higher than this value, it will have a negative impact on the safety of mother and baby during pregnancy. For example, pregnant women are more likely to suffer from pregnancy-induced hypertension, which needs to be judged according to their actual situation. Some pregnant women have been injected with HCG in the early pregnancy to protect the fetus, so it is possible to have a high HCG value when doing Tang screening.
Solution: If the HCG value in Down's screening is high, it is necessary to combine other judgment methods to evaluate the risk of Down's syndrome through non-invasive or amniocentesis.
14. It is good to double HCG, but what about the decrease of progesterone?
It is good for HCG to double and progesterone to decrease, which indicates that the embryo develops normally, but the function of HCG to promote progesterone is not good. Or congenital luteal insufficiency, the doctor may rule out the cause and come to the conclusion that if progesterone is lower than 20ng/ml, progesterone can be supplemented. If it is between 20 and 25 ng/ml, but there is no bleeding, no bad secretion and no abdominal pain, it is generally not necessary to supplement progesterone.
Rest also has some protective effects on the fetus. This is especially true for expectant mothers who are prone to miscarriage. Rest can prevent blood from flowing to the limbs, and the blood flowing to the uterus will increase to ensure the baby's nutrition. If you don't move, the uterus will not be squeezed by internal organs, and the embryo will be more stable under the condition of low progesterone.
15. Little knowledge: How low is progesterone to protect the fetus?
Progesterone:
Large unit nanogram/ml
Small unit nanomole/ml
Hospitals usually do this:
Taking 25 units (80 small units) as the standard line, if the progesterone is less than 25 units (80 small units), doctors will recommend abortion, and individual hospitals will only have abortions if it is less than 20 units (60 small units). The way to protect the fetus is generally oral administration or injection of progesterone, or both.
Sixteen, progesterone is normal, HCG doubled is not good?
Progesterone is normal, but it is very rare to double HCG. Because HCG promotes the production of progesterone, HCG is not good, and progesterone is generally not good. We will specify the following from two situations:
1, progesterone is normal, and HCG doubling is "relatively" bad. What do you mean, one day you went to test, and the value went up, but it couldn't reach the multiple, and the difference was 1200, which was relatively poor. If your HCG has reached tens of thousands, it will not be so fast to start doubling, and the speed will drop, which is normal.
2. Progesterone is normal, and doubling HCG is "absolutely" bad. Absolutely not good, that is, the value is only in a range, for example, 8 days, doubled, which is not very good. First rule out ectopic pregnancy, and then maybe there is something wrong with the embryo. At present, many hospitals only supplement progesterone, and rarely supplement HCG, because low HCG is likely to make the embryo itself worse, and it is of little value to protect the fetus.
17. what should I do if progesterone drops and HCG doubles?
HCG is not doubled, but decreased, and progesterone is also decreasing. In this case, the doctor suggests that you have an abortion first. If you still don't get better after taking measures to protect the fetus, you will also be advised to give up and have an abortion as soon as possible.
Because in this case, it is very likely that the embryo itself is not good, and it is meaningless to protect the fetus. If forced abortion, even if the abortion is successful, the fetus will face more tests in the third trimester of pregnancy, and even fetal arrest will occur. If you have an abortion later, the expectant mother will also increase the risk.