How Do Pregnancy Tests Work?

What's hCG? Find out how it plays a big role in confirming your pregnancy.

home pregnancy test kit, which you can buy at any drugstore, is a simple, fast, and private way to confirm that you're expecting. It works by testing your urine for the hCG hormone that's produced during pregnancy. If the test detects a certain level of hCG, it will show a positive result, confirming that you are pregnant.

However, if the test is negative, you may still be pregnant. You may have done the test too early, before there is enough hCG in your urine. Wait a few days and repeat the test. If it is still negative and you haven't gotten your period, something else may be happening in your body. Certain medications and illnesses can cause you to skip a period, as can excessive exercise, low body weight, early menopause, birth control pills, or stress.

After testing positive on a home pregnancy test, some women like their doctors to confirm their pregnancies. Your doctor can perform a simple blood test that can detect hCG in even smaller amounts than a home pregnancy kit can.