One reason for a false positive pregnancy test may be what is called a chemical pregnancy. This means you may have had an early miscarriage which manifests itself as your period when the time comes. Some pregnancy tests are so sensitive that they can catch the earlier chemical composition of a pregnancy. This is why doctors often advise women to test for a pregnancy if they have definitely missed their period. Testing before you have missed a period may lead you to believe that you are pregnant only to have your hopes dashed when you get your period a few days after.

Chemical interference may also cause a false positive pregnancy test result. Some women need shots of the hormone Human Chorionic Gonadotropin to treat infertility. Make sure that the hormone is fully gone from your system before you take a test to avoid false positive pregnancy test results.

Evaporation lines in the indicator stick may also deceive you that you have a positive pregnancy test. This is not technically a false positive pregnancy test but it can lead you to believe that you are pregnant. Make sure to follow the instruction son the home pregnancy kit to fully utilize the kit and to have no doubts regarding the results.

Home pregnancy test kits are not foolproof and that is why you need to check with a licensed obstetrician to confirm your pregnancy. It I always best to consult a doctor if you suspect that you are pregnant and not just rely on the home pregnancy kit.