There are a few things that can cause a negative pregnancy test. 1) test not taken properly, 2) medications, 3) timing of the test. To ensure the best results:
- Take the test in the morning, if possible, because your hCG (pregnancy hormone) levels are at it's highest
- Don't drink a bunch of fluids before taking the test because it will dilute your urine and can affect the results
- Take the test no more than 1-2 days before expected period. Although some test say that you can see results up to 5 days before your missed period the percentage of accuracy is very low.
- urinate for as long as possible on the foam like strip
- wait for the results