What about pregnancy turns women into a Playmate?

My job requires me to look at photos of pregnant women all of the time and they're beautiful!  I loved being pregnant and I loved showing off my new figure.  There's a weird, in my humble opinion, trend emerging though.  I can't flip through ten pregnant photos without seeing something that belongs on the pages of Playboy. 

We're not talking about full-frontal or anything, but I'm talking about elaborately staged bedroom scenes, literally, with a scantily clad mom-to-be.  In 99% of the cases, she's gorgeous.  Obviously she's celebrating her pregnant body.  But when I look at the rest of the pictures on her profile, there's nothing that suggests that her inner sex kitten was so close to the surface until her belly popped out.  So what gives? 

Does being pregnant release inhibitions about body issues since there is supposed to be extra weight and curves?  I'd love to know the age of these sexy moms-to-be.  Are their photo shoots motivated by a younger generation's provocative style?  I mean seriously - if I see one more butt-crack/cleavage combo on a 15-year-old at the mall, I might barf.  You've got a great body, but no need for me to see it almost nude.  Where are your parents, young lady?

My last question is what drives these women to post their photos in such public forums?  The photos I used were on a photographer's site, so they're slightly less racy and a smidge more artsy than others I've seen, but still.  Maybe I'm getting old.  I don't see these things as inappropriate, just private.  When I show my kids my pregnancy photos - particularly ones I share with the world - I'd be fine with nudity in the "pregnant body is beautiful and nothing to be ashamed of" sense, but the trend is hedging more towards, "the pregnant body is beautiful and Daddy couldn't wait to be done taking pictures so we could practice making your little sister."   Imagine your own mom in lingerie, sprawled out on a bed, covering only her nipples with her fingertips giving the camera bedroom eyes.  Are you cool with that?  Imagine that picture on Facebook for all of her friends and family to comment on.  Now imagine you are your child in 20 years and the mom in the picture is you.  Just sayin'...