Early pregnancy test strips can also be wrong, for example, the test strips used are out of shelf life or the test method is incorrect and so on there may be errors. Early pregnancy tests are the most commonly used method of detecting pregnancy, and are used to determine pregnancy by detecting HCG in the urine. The use of early pregnancy test strips generally need to use morning urine, because morning urine is more concentrated, the test results will be more accurate, other time of the day due to drink more water, urine will be more dilute, may affect the test results. Also when buying early pregnancy test strips, you should look at the shelf life on them, if they have expired, it may have an impact on the test results and lead to incorrect results. Usually the results of early pregnancy test paper is only as a reference, if you want to clearly determine whether the pregnancy, it is recommended to go to a regular hospital to draw blood and pelvic ultrasound, the results will be more accurate.