If you think you are pregnant, you probably have already missed your period, in which case you can take a pregnancy test whenever you'd like. If you have not yet missed your period, you should wait until you do (or don't) to take a pregnancy test. While you can take an at-home test as early as six days before your missed period, the accuracy at such an early date is very low. It is best to take the test after missing a period. Try waiting several days after missing a period and taking one, the accuracy at this point is at it's peak.