Pregnancy Test Accuracy

Pregnancy test kits are widely popular owing to their ease of use and affordable cost. Most women rely on these tests to confirm their pregnancy. Over the years, these tests have proved to be an accurate medium of detecting pregnancies. However, there are various factors involved when we talk about accuracy and sensitivity. These factors can greatly affect the results of the test. In this article, we will discuss these factors and will also list the most accurate pregnancy test that is available.

Factors Affecting Pregnancy Test Accuracy

Earliest detection of pregnancy is done by checking the presence of hormone named Human Chorionic Gonadotropin (hCG). This hormone is secreted by the placenta of the developing embryo. The levels of this hormone are very low during the initial days of conception. The amount of hCG before you miss your period is about 5 to 20 mIU/ml. However, after that, the amount of hCG goes on doubling every two days. The home pregnancy test kits that are commercially available in the market are capable of detecting hCG levels above 20mIU/ml. Hence, if you get a test before you miss your period, you are most likely to end up with an inaccurate result. In this case, the test will fail to detect the very small amount of hCG in your urine, as a result it will show a negative even though you are pregnant. This is called false negative pregnancy test.

Similarly, failure to follow the instructions on the test properly may also result in incorrect test result. Although, most tests have an indicator for an invalid test, you may sometimes get a false result for pregnancy testing if you do not follow a proper procedure. Holding the test sample for a long time may sometimes (though very rarely) lead to a false positive result. Also, very diluted urine may also not produce reliable results as the very small amount of hCG present in it cannot be detected by any of the tests. First morning urine should be taken as a sample for detecting pregnancy as it is in the most concentrated form. Besides, the best time to take a test would be a week after the missed period, as the amount of hCG at that time is sufficient enough to be detected on the test.

Most Accurate Pregnancy Test

Blood test is the best test as blood test for pregnancy accuracy is maximum. Besides, it is also the earliest test as it can produce reliable results before you miss your period. Among the other home pregnancy test kits available in the market, First Response Early Result was found to be the most sensitive and accurate test. During the research conducted by University of New Mexico at Albuquerque, it gave accurate results in 95% of the cases that were tested within two days of missed period. ClearBlue Easy was the next best pregnancy test with an accuracy of 80% for the first two days after missed period. Results produced by other test kits at the same time was about 16%. However, if you wait until a week after your missed period to perform a test, then the brand of the test wouldn't matter much, since all the known brands can give you accurate results in 99% of cases.

Some websites have a pregnancy accuracy chart that may help you in studying the accuracy and sensitivity of the various tests. However, we recommend that you wait until a week after your missed period so that external factors like brand of test kit wouldn't matter much. Besides, the result that you obtain at that time is likely to be highly reliable.