Tests work by looking for levels of a hormone (HCG) which is produced when you are pregnant ... yet it could send mixed hormonal messages which mean you get a faint but positive message from one test ...

If your pregnancy test is expired, it might give a false negative result. This is because the antibodies in the test that react to hCG hormones slowly evaporate over time - eventually there will ...

an at-home pregnancy test can measure hCG levels with 97 to 99 percent accuracy. Pregnancy tests with blue or pink dye typically show one line if the result is negative and two if hCG is detected ...