I'm wearing two sorts. Neither of them are granny type and I wear size 14-16. Plain old ordinary bikini briefs are comfy and sit under your belly. String bikinis are my fave, prenant or not but they are harder to get in the larger sizes. They usually have some elasticy kinda material on the sides holding the two triangles together so they stretch better than normal undies. If you go for these just make sure they have the elastic strings rather than cotton ones which wont stretch. You can usually get them at Best and Less, Big W or Kmart, sometimes in multipacks (if you are lucky).