Blood tests can detect pregnancy earlier than a home pregnancy test, about six to eight days after ovulation although it takes a little longer to get the results than with a home pregnancy test.
There are two types of blood pregnancy tests:
A qualitative hCG test simply checks to see if hCG is present. Doctors often order these tests to confirm pregnancy as early as 10 days after a missed period. However, some of these tests can detect hCG much earlier.
A quantitative hCG test (beta hCG) measures the exact amount of hCG in blood. It can find even very low levels of hCG. Because these pregnancy tests can measure the concentration of hCG, they may be helpful in tracking any problems during pregnancy. They may also be used to monitor a woman after a miscarriage when hCG levels fall rapidly.
Note: Whilst labs tests are effective earlier in pregnancy, appointment times and results can mean that a home pregnancy test will be as quick. Check what your local health care provider offers to decide which suits your circumstances best.