Some tests are more sensitive and can indicate a positive pregnancy test sooner than others, but best practice dictates that you wait until the day of your expected period to take a pregnancy test. This time will allow a pregnancy hormone, which tests detect in urine, to build and produce a positive result.
If you believe you may be pregnant and previously took a test that resulted negative, testing again can give a more accurate result.
What Is HCG?
Human chorionic gonadotropin, or hCG, is a hormone exclusive to pregnancy that aids the body during the pregnancy journey.
According to the Cleveland Clinic, “Once your placenta begins making hCG, it triggers your body to create more estrogen and progesterone. Together with hCG, these hormones help thicken your uterine lining and tell your body to stop releasing eggs. The correct balance of these three hormones sustains and supports the pregnancy.”
HCG levels are also helpful for medical professionals to confirm pregnancy and understand how a pregnancy is progressing.
How Does A Pregnancy Test Work?
Pregnancy is tested either through urine or blood. However, no matter which test is used, the same hormone is examined: hCG.
Once hCG has built up enough in the body, it can be detected in pregnancy tests.
If not enough hCG is present, the test may give a false negative. Therefore, testing at the appropriate time is necessary for accurate results.
Lastly, a false positive can occur after miscarriage, this is why receiving an ultrasound in combination with a quality pregnancy test is important to confirm pregnancy.