Choosing the best early pregnancy test requires consideration if women want to use a home test. Blood tests are more accurate during the early days of pregnancy after embryo implantation has occurred. For urine tests, the best test has the highest sensitivity level, or level at which the test detects hCG (human chorionic gonadotropin). Blood tests detect hCG when it is present in amounts of 5 mIU/ml (million international units per milliliter). Most early pregnancy tests that evaluate urine don’t test positive unless a women has 12.5-20 mIU/ml of hCG, and standard tests won’t detect levels under 40-50 mIU/ml.
In choosing an early pregnancy test, women should define what “early” means for them. Many home test manufacturers advertise they’ll test accurately within a day or two of a missed period. This is approximately 12-14 days after conception. If women know when conception may have occurred, waiting two weeks after that date means that most tests could be appropriate. If the goal is to test much sooner, such as four or five days after conception, it may be hard to get a completely accurate result on any urine test. Blood tests are the best bet at this very early stage.
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As a pregnancy advances in the first month, hCG levels increase rapidly, and in many women, the hormone amount doubles every couple of days. When an early pregnancy test doesn’t show a positive result, a few more days could raise hCG levels to the sensitivity of the test. Not all women have exactly the same levels, but generally, amounts of this hormone show a consistent increase. Within a matter of a few weeks, most pregnant women have hormone amounts that are detectable by the average test.
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There are really only a few extremely early pregnancy test kits on the market. Again, these aren’t as accurate as blood tests, but they may detect pregnancy about seven to nine days after implantation, which occurs a day or two after conception. These few tests are heavily advertised as detecting pregnancy early, but what women should really look for is the hCG sensitivity level. This isn’t always advertised on test boxes, but online research or calls to manufacturers of tests can yield this information. Finding the lowest sensitivity is the key to choosing the most accurate early pregnancy test.
Sometimes less sensitive tests create a very faint line that suggests pregnancy. This is usually a positive result. Women can verify results with a more sensitive test, or they could recheck in a couple of days.
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The disadvantage of the early pregnancy test is some women will miscarry before their first period. With early detection, this pregnancy may be noted, and it can be disappointing and difficult when it ends. There are many women who prefer to wait until a missed period to test because they don’t want to get excited before they know for certain that a pregnancy has a better chance of continuing.