Pregnancy occurs when the sperm from a male fertilizes the egg from a female and this fertilized egg is implanted in the uterus wall. This process happens as a result of sexual intercourse during the period when a woman’s egg is maturing and is released into the fallopian tubes. In order to test if a woman is pregnant, one would need to check the levels of several different hormones in her blood. This is done at the early stage because it may not be possible to see the growing embryo in an ultrasound scan.
A blood test for pregnancy is done by testing the level of a hormone known as HCG. The full form of HCG is Human Chorionic Gonadotropin hormone. This hormone is known as the pregnancy hormone as it is a key marker to detect pregnancy in a woman. It is produced by the embryo and can be detected within 10 days of fertilization taking place.
In order to test the blood for this hormone, the doctor will draw a sample of your blood from your forearm. This will be done by inserting a syringe which is attached to a vial. The vial will collect blood as it pours through the syringe. The insertion of the syringe will cause a pin prick sensation. Other than that, this procedure is painless. The collected blood will now be analyzed in a laboratory.
The analysis can occur in two ways. One way is to check the quantity of various components in the blood. This is costlier and may take more time. It is known as a quantitative test. The second procedure is known as a qualitative test, which aims to simply confirm or deny the existence of the HCG hormone in your blood. The quantitative test is more accurate as it can judge the level of the HCG hormone as well as other markers that would give information on the progress of a pregnancy. The qualitative blood test is as accurate as a urine test and simply gives a yes or no answer.
Errors could sometimes occur when testing the blood for the HCG hormone. This happens more in the case of the qualitative test. If you are under some sort of medication that raises the level of the HCG hormone in your blood, the test will show a positive result. This may also be the case in some second time mothers who have traces of HCG in their blood.
Submitted by M H on April 13, 2010 at 10:35