This law states that common science tells us that pregnancy begins two weeks before conception. You can't tell if the baby is going to survive til about the 20th week. And this effectively makes it so the 18th week is the furthest you can go with it, so you may have to carry a baby that wouldn't survive anyways. http://thenewcivilrightsmovement.com/pregnancy-begins-2-weeks-before-conception-now-the-law-in-arizona/politics/2012/04/13/37993