Many American women, until they get pregnant, have no idea that they are entitled to no paid leave under current law. Indeed, a study from Harvard University last year found that of 168 nations worldwide, the United States is one of only four whose government doesn't require employers to provide paid maternity leave. The others are Lesotho, Papua New Guinea and Swaziland.
Not exactly great company. I would question, though, whether this is really something we want to be requiring employers to provide. Insofar as paid maternity leave is something we think we need (and it should be!), funding it is a shared responsibility that government needs to undertake, not employers. If your welfare state rests on a foundation of coercing corporations into providing benefits, you're probably going to wind up with a lot of economic distortions and a pretty crappy welfare state to boot.