How early can someone take a pregnancy test and it be reliable?

Pregnancy test that are conducted too early in pregnancy might give inaccurate results. This is because the level of hCG in th eurine or blood might be too low to be detected by the test.

To ensure reliable result it's best to wait until at least a week after your missed period before taking a pregnancy test. For even greater accuracy, waiting until the day of your missed period is preferable.