Home pregnancy tests check the urine for hCG. The amount of hCG increases daily in pregnant women, so most tests are fairly accurate about two weeks after ovulation. Laboratories may use one of two blood tests to confirm pregnancy. A qualitative hCG blood test checks to see whether or not the hormone is present. Its reliability is comparable to a urine test. A quantitative blood test (the beta hCG test) measures the exact amount of hCG in the blood. It can detect even tiny amounts of hCG, making it extremely accurate. Blood tests may confirm a pregnancy as early as six to eight days following ovulation.