It may sound dramatic but the Mirena coil really transformed my life. After two children my periods became so heavy that it was causing me great difficulties. The coil stopped the bleeding, apart from a very light two day period (one small lillet a day). No major hormonal problems, but then I hadn't any beforehand, so can't be helpful on that front. Also no weight gain. However, it is painful to have put in - make sure you take painkillers and be prepared to spend the rest of the day in bed (like heavy period pain). All totally worth it, in my opinion.