Blood pregnancy tests can pick up hCG earlier in a pregnancy than urine pregnancy tests can. Blood tests can tell if you are pregnant about 6 to 8 days after you ovulate (or release an egg from an ovary).
Urine tests can determine pregnancy about 2 weeks after ovulation. Some more sensitive urine pregnancy tests can tell if you are pregnant as early as 6 days after you conceive, or one day after you miss a menstrual period.
There are many types of home pregnancy tests that can be bought over-the-counter at drug or discount stores. Some pregnancy tests involve collecting your urine in a cup and dipping a stick into the urine or putting some of the urine into a special container with an eyedropper. Other pregnancy tests are done by placing a stick into your urine stream.
Pregnancy tests vary in how long you have to wait for the stick or container to turn a certain color or have a symbol on it (like a plus or a minus). All tests come with written instructions. Most pregnancy tests also have toll-free phone numbers to call if you have any questions about how to do the test or read the results.
Home pregnancy tests (HPTs) are very accurate. Most brands of home pregnancy tests say they are 97 to 99 percent accurate, but this can vary with actual use. Each brand of pregnancy test varies in how sensitive it is in picking up the pregnancy hormone hCG. If a pregnancy test is not done correctly, it will be less accurate. Always check the package to make sure it is not past its expiration date -- if it is, it will not be accurate.
Most brands of home pregnancy tests tell users to do the test again in a few days, no matter what the results.
If you use a home pregnancy test too early in your pregnancy, you may not have enough of the pregnancy hormone hCG in your urine to have a positive test result. Most home pregnancy tests will be accurate if you test yourself around the time your period is due (about 2 weeks after you ovulate, or release an egg from your ovary). You can get a negative test result if you are not pregnant or if you ovulated later than you thought you did. You may also have problems with the pregnancy, which affects the amount of hCG you have in your urine. If your home pregnancy test is negative, test yourself again within a few days to one week. If you keep getting a negative result and you think you are pregnant, talk with a healthcare provider right away.