Buzzfeed has 70 photos of signs at various Walk for Choice events. Many of them are unsurprisingly crude. One has the self-evident truth clause from the Declaration of Independence which notes that "all men are created equal" and endowed with "the right to life."
Here's photo album from the Walk for Choice in Grand Rapids.
One sign (I believe) reads "Because I would suck as a mother, I stand with Planned Parenthood."