Blood tests can pick up hCG earlier in a pregnancy than urine tests can, so you could possibly find out if you are pregnant about 6 to 8 days after you ovulate (or release an egg from an ovary) and before you miss a period. That means they can provide a more accurate answer very early on in the pregnancy, within about 7-12 days after conception.

Even with pregnancy blood tests, there are 2 types. A quantitative blood test (or the beta hCG test) measures the exact amount of hCG in your blood. It can find even tiny amounts of hCG which makes it very accurate.

Qualitative hCG blood tests only check to see if the pregnancy hormone is present or not, so it just gives a yes or no answer. The qualitative hCG blood test is about as accurate as a urine test.
Either test typically requires sending the blood sample to the lab for analysis and may take anywhere from a few hours to more than a day to get the results.

Your doctor may choose to use a blood test to match hCG levels as the pregnancy progresses since hCG levels usually double about every 2 days during the first few weeks of pregnancy. For instance, if the levels don’t rise, it may indicate a problem with the pregnancy. Or, extremely high hCG levels may mean a woman is carrying twins.

OK, you know you are pregnant.

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