How soon can I check a pregnancy test?

Pregnancy tests measure the amount of pregnancy hormone (human chorionic gonadotropin or HCG) in your system. HCG is produced by the embryo and is first detectable in your bloodstream as early as 6-8 days after the egg is fertilized.

Home pregnancy tests measure the amount of HCG in urine. These tests cannot measure a level lower than 25, so they do not become accurate until the day you expect your period, at the earliest. A negative result before then is meaningless, since there would not be a high enough level of HCG to detect even if you were pregnant.

Blood pregnancy tests can measure any number from 0 on up. That's why they are more sensitive, and can become positive 6-8 days before your period is expected.