Can you imagine what kind of stars would have to align for hot pregnant chick mudflaps to take off?
Just for fun sometime on the freeway, try and figure it out: whose the typical customer for regular hot chick chrome mudflaps? What does he drive? What's the likelihood that he's a great, there-for-her baby daddy?
Now ask, who would likely buy hot pregnant chick mudflaps ironically, probably as part of that whole Ashton Kutcher/Von Dutch trucker hat thing? Now what does he drive? Have you ever seen a "mudflaps on a Prius" look that actually worked? You see the problem. And we haven't even begun talking about where you'd sell them.
So until all the giant, tricked out pickups and semis are converted to grapeseed biodiesel, and all the nation's freeways start smelling like french fries and aromatherapy candles, and all the truckers--ironic and otherwise--stop cheatin' on their belly-popping baby mamas with those scrawny airhead waitresses and become enlightened, involved dads, we'll just have to buy the world a Diet Coke and furnish it with love--and make do with the "sexy 'n showing" pregnant mudflap chick t-shirts from the Santa Barbara-based pioneer of the "pregnancy slogan t-shirts" industry Preggers 'n Proud.
"Sexy 'n Showing" t-shirt or wifebeater [sic] versions, $26.50, in maternity sizes only, duh [preggersnproud.com]
Also available: "Good dads are HOT" t-shirts, which I don't think you can legitimately buy for yourself, and baby-sized t-shirts with "Mama's got my back/And so does Daddy!" which you can. Buy, I mean, but not for yourself because they're size 6 months or whatever and... you know what I mean.
Speaking as a woman who spent much of her pregnancy searching for the sexy-pregnant-chick tshirt I had once seen that did not have any silly words on it (and that's a really hard thing to Google without learning things you never wanted to know), I know women who would buy those ironically. Quite a few of them, actually. Maybe it's a California thing.