I have lost a lot of weight. I started out at a 46C. Now, close to 100 lbs lost, I'm 38DD. I think they helped. I also kept some of the leg/but fat and that has helped with my shape. However, look at the body shape of your nearest female relatives: if they are hour glass types, start HRT. The mobs will help breast development. It they are Ovoid, maybe keep losing a little weight.
Jen