Ever wonder how pregnancy tests work?
There are several varieties of pregnancy tests -- some are done using urine and some, blood. Pregnancy tests can be performed at home or can be done in a lab. All of the commercially available tests detect human chorionic gonadotropin or hCG, a "glycoprotein."
Read the entire article here- http://www.ivillage.com/pregnancy-how-do-pregnancy-tests-work/6-n-138622?ice=iv:mb:msg:kp