Present in the blood from the 10th day of pregnancy, and a little later in the urine, it is this hormone (hormone chorionic gonadotropin) that is sought in pregnancy tests, whether blood or urine.
In early pregnancy, the hCG rate doubles every two to three days. It reaches its maximum at the end of the third month of pregnancy, then slowly goes down again.
A precise dosage of this hormone can accurately date the pregnancy. Between the 15th and the 17th week, the hCG assay also makes it possible to evaluate the risk of trisomy 21 and thus to prescribe, or not, an amniocentesis.
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