Usually the ads are catered to what the individual members have been looking at in their search engines... specifically Google.
If you're seeing scantly clad women in provocative poses, then there is something in your Google search history that's triggering those results.
I was getting hemp gummy ads be cause I just ordered some hemp chews for my pups. I believe I was getting the weather girls because I recent searched for a story about a local weather forecaster.
If you're seeing scantly clad women then... it means you're a pervert.