Home pregnancy tests measure the presence of a telltale hormone in your urine called human chorionic gonadotropin (hCG). HCG is a hormone found only in pregnant women. It is produced by cells in the uterus and is responsible for signaling the ovaries to produce estrogen and progesterone to help your fetus grow. Many home pregnancy tests claim to be 99 percent accurate on the day you miss your period. It most home pregnancy tests don’t consistently spot pregnancy this early, the tests are considered reliable when used according to package instructions one week after a missed period. The hormone is released in a pregnant woman’s urine.
There are two main types of pregnancy tests. Both are commonly used to detect pregnancy.
Home pregnancy tests are available at your local drugstore or pharmacy and at some large department stores. Blood pregnancy tests are performed by health care professionals in an office or a clinic. Home pregnancy tests are usually about 97% accurate, but this varies from brand to brand. The amount of human chorionic gonadotropin (hCG) in your body then increases rapidly over the next few weeks, doubling in amount about every two days. HCG can also be detected in your blood, around 10 days after you conceive, and your GP may advise you to have a blood test.Pregnancy blood tests are performed health clinic. They detect pregnancy by measuring hCG levels in your blood. The most sensitive test of pregnancy is best performed by a laboratory using a sample of your blood.
Blood tests performed at your clinic have a 99% accuracy rate and can detect pregnancy earlier than most urine tests. Blood tests can be performed 7 days after you ovulate and still provide accurate results. Some urine tests can be used on the first day that your period is due, however, it is unlikely that you will achieve that 97% accuracy rate if you test so early. The quantitative blood test detects pregnancy by measuring the exact amount of hCG in your bloodstream. It can also be used to detect how far along you are in your pregnancy. It does not measure your hCG levels, and only provides a yes or no answer as to whether or not you are pregnant. Home pregnancy tests only check hCG levels, not progesterone. They are completely different hormones.