birth control
"I have been on Depo Provera for about 8 years and I've loved it.  I haven't had any cramps but I do spot for a couple weeks before my shot is due.  I never gained weight, although I should note that I have a very high metabolism.  However, my doctor recently had me do a bone density test and the results were not good.  I'm 25 and my bone density levels were very close to those with osteoporosis.  Studies show this is reversible once you are off the shot, however, the studies are not clear about the long term effects.  So, unfortunately, my doctor no longer wants me on the shot and I am currently looking into another form of birth control."