Human chorionic gonadotropin (hCG) is a hormone that is produced by the body of a woman during pregnancy. HCG appears immediately after fertilization and allows you to determine pregnancy for 4-5 days. HCG is produced by chorion and continues to grow until 12-13 weeks of pregnancy - the maximum rate of the hormone at this moment is 90,000 mU / ml, after which the index begins to decrease. For example, the norm of hCG at week 19 already varies within the range of 4720-80100 mU / ml. The norms of HCG on days and weeks allow you to monitor the development of pregnancy in the first trimester, to identify possible pathologies and developmental abnormalities.
Definition of hCG
Determine the level of hCG in several ways. The most accurate results are obtained by a blood test, which allows you to identify a pregnancy before the delay in menstruation. Investigating the norms of hCG for obstetric weeks, an experienced doctor can accurately determine the duration of pregnancy and possible pathologies ( fading of the fetus , threat of miscarriage).
Less accurate data gives an analysis of urine, although it is on it that all home pregnancy tests are based. It is worth noting that if the definition of the hormone in the analysis of blood on HCG makes it possible to follow the course of pregnancy, then urine analysis does not provide such accurate data.
Rates of beta-hCG for weeks:
- 1-2 weeks - 25-156 mU / ml;
- 2-3 weeks - 101-4870 mU / ml;
- 3-4 weeks - 1110-31500 mU / ml;
- 4-5 weeks - 2560-82300 mU / ml;
- 5-6 weeks - 23100-151000 mU / ml;
- 6-7 weeks - 27300-233000 mU / ml;
- 7-11 weeks - 20900-291000 mU / ml;
- 11-16 weeks - 6140-103000 mU / ml;
- 16-21 week - 4720-80100 mU / ml;
- 21-39 weeks - 2700-78100 mU / ml.
All established norms of HCG, whether it is analysis at week 4 or at 17-18 weeks, are relevant for the normal course of a single pregnancy. If the embryos are two or more, the hormone indices will be several times higher. So, for example, in normal uterine pregnancy, hCG at 3 weeks averages 2000 mU / ml and continues to double every 1.5 days. Thus, by 5-6 weeks, the norm of HCG of the order of 50,000 mU / ml is considered normal.
It is worth noting that a low hCG can indicate the termination of pregnancy, that is, the fading of the fetus. Insufficient growth of the hormone also indicates an ectopic pregnancy and a threat of miscarriage. At a period of 15-16 weeks, the level of hCG, the norm of which should be in the range of 10,000-35,000 mU / ml, in combination with the results of other tests used to identify pathologies in the development of the fetus.