What are Pregnancy Blood Tests?

Pregnancy blood tests and pregnancy urine tests are very similar in that they test of the same thing. Both tests test for hCG or human chorionic gonadotropin. hCG is released after the egg is fertilized and is implanted in the uterus (can take up to 12 days after fertilization to be implanted.) When this happens, hCG is released by the embryo and in a few days makes its way into your urine and bloodstream.

Pregnancy blood tests can detect hCG in your bloodstream usually a few days before a urine pregnancy test can detect it in your urine. There is also research on the web that blood tests can actually determine pregnancy better than urine pregnancy tests (even though, most of the time, both are correct.)

Another interesting thing to know is that pregnancy blood tests actually can determine two different things about hCG in your body. Qualitative pregnancy blood tests determine whether hCG is in your blood or now, similar to a urine pregnancy test. Quantitative pregnancy blood tests determine exactly how MUCH hCG is in your blood.

The reason your doctor might want to know how much hCG is in your bloodstream is because as you proceed through your 1st trimester of pregnancy your hCG levels will increase (then gradually decrease over time). If for some reason you are not at the “average” level of hCG in your body, it might be a indication of pregnancy problems. This helps the doctors determine what to look out for, and make sure the baby is healthy.