Mental Floss

How Do Pregnancy Tests Work?

Yelena Melnichenko

Ever wonder what the very first pregnancy test was like? Or how, exactly, home kits work? Or—most important of all—how reliable they really are?

Look no further than this easy-to-understand (and visually entertaining) TEDEd video by Tien Nguyen, which explains the history of, and the science behind, these all-important plastic indicators.