With the help of an analysis for the content of chorionic gonadotropin in biological fluids, it is possible to establish the presence of pregnancy, as well as the nature of its course. It makes sense to donate blood for analysis or do a home rapid test only until a certain period of time.
Change in the concentration of chorionic gonadotropin in biological fluids
After the embryo is implanted into the wall of the uterus, its active development begins. At the same time, the body is rebuilt, the hormonal background changes. One of the signs of pregnancy is an increase in the concentration of chorionic gonadotropin in the urine and blood. Before its onset, hCG is contained in biological fluids in minimal amounts.
After implantation of the embryo into the uterine wall, the concentration of hCG in the blood and urine increases exponentially during each subsequent week. In order to establish the presence of pregnancy, you can donate blood for the presence of a specific hormone within 4-6 days after conception.
A home rapid urine hCG test has a much lower sensitivity to gonadotropin. It can be carried out only from the first days of delayed menstruation, but not earlier. Only in this case, you can count on obtaining a reliable result.
A blood test for hCG is the most accurate method for diagnosing pregnancy and the nature of its course. There are certain tables in which all the values of the concentration of hCG are prescribed, which are characteristic for a particular period. If the indicators obtained as a result of the analysis differ significantly from the norm, this may indicate the presence of certain violations.
How long can you donate blood for hCG?
Women at risk are forced to periodically donate blood for hCG. This is necessary in order to track the dynamics of an increase or decrease in the concentration of the hormone in biological fluids. Deviations of indicators from the norm can be associated with serious pathologies.
An insufficient increase in the concentration of chorionic gonadotropin in the blood in the early stages of pregnancy may indicate the existing threat of spontaneous termination. Cessation of growth or even a decrease in the concentration of hCG in the blood may indicate the death of the fetus.
It makes sense to do an analysis for hCG only before 7-9 weeks of pregnancy. After this period, the level of the hormone begins to gradually decrease. At the same time, the rate of its decrease may differ somewhat in individual cases.
For a period of more than 7-9 weeks, there is no need to donate blood for hCG also because during this period, pregnancy is already, as a rule, established, and its development can be tracked by the results of ultrasound studies, which is more informative.
Blood for hCG is subsequently donated once only at 12-14 weeks of pregnancy. In this case, an ultrasound scan is additionally prescribed, since the necessary data on the development of the fetus can be obtained only by simultaneously carrying out both types of diagnostics and comparing their results.