Home pregnancy tests are not all equal when it comes to sensitivity. If you want to choose the most sensitive pregnancy test, you’ll typically need to compare pregnancy tests based on the minimum level of human chorionic gonadotropin (hCG) they can detect. HCG is a hormone that is secreted in increasing amounts in a pregnant woman’s urine. Generally, those that detect hCG levels that have reached 20mIU/ml or less are the most sensitive of the home pregnancy tests and may be able to deliver accurate results a couple of days before your period is due, depending on when you ovulated. If you want the most accurate early result, however, you may choose to have a blood test performed in your doctor’s office.
Most of the home pregnancy tests on the market are capable of providing highly accurate results within a few days of a missed menstrual period. In fact, there are some that are advertised as producing accurate results as early as the day of a missed period. Some women have even received a positive result before they’ve missed a period. To get an accurate result on a pregnancy test sooner rather than later, you will typically need to choose a pregnancy test that detects lower concentrations of hCG.
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HCG is produced after an egg is fertilized and implanted in a woman’s uterus. Levels of the hormone are low at first, but gradually start to rise. In many cases, fertilized eggs implant within about a week to 10 days of ovulation. Some women, however, may not expect their periods for up to 16 days after ovulation. As such, the most sensitive pregnancy test may be able to detect pregnancy after implantation but before a woman has missed a period.
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When you’re trying to choose the most sensitive pregnancy test, you may find many that claim to detect pregnancy when hCG levels reach 50mIU/ml or higher. This type of test may be accurate, but it is not the most sensitive pregnancy test. You may get a positive result earlier by choosing a test that detects pregnancy once hCG levels reach 20mIU/ml. Depending on when an egg implants, this type of test could possibly detect pregnancy before your period is due. There are even some test kits that are advertised as capable of detecting hCG levels below 10mIU/ml; these tests are even more sensitive.
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You may also consider visiting a doctor when you want to get an early result on a pregnancy test. While many doctors perform urine tests to detect pregnancy, asking for a blood test may produce accurate results earlier. A blood test typically produces accurate results within seven to 12 days of ovulation or conception.