Write some JS to delay loading the adverts until after all of the other content on your page(s) has been loaded and displayed. JQuery (especially) makes it easy to delay this kind of stuff and do the <div> injections well after your page is visible in the client browser.

I coded one two (three?) years ago for a contract, and it worked like a charm. Used it for tracking pixels, Google tracking, and a bunch of other stuff.

Surprised this kind of snippet isn't readily available on the intertubes.