As GonnaBeGiant pointed out, insulin can be problematic. If you're on a high-fat diet while taking insulin, it's really easy to put on fat. In addition, Metformin (a blood-sugar-regulating medication for diabetics) can inhibit mTOR.
For the girls, I think birth control pills may play a factor.
I can double that,my Gf is getting ripped with her 4 pack showing nicely but her hip fat is the same as before..BC pills seem to mess up wioth the hormones as it is supposed to.
I'd think any medication that may have an effect on hormones and thyroid would most definitly cause problems. I'd also think anything that messes with testosterone or estrogen levels as well.