I have not had a period in 2 months and the last one was very light and lasted only 3 days. I have taken 4 pregnancy tests and they are all negative. I am NOT trying to conceive and I am relieved about the test results but also worried about my missed period. What would cause that? I have also been gaining a lot of weight. I'm not exceedingly stressed, I'm not pregnant. What's the deal??

Its best to go have a chat with your dr if you miss more than one period. Periods can stop, being obese can do it, or being underweight, as well as stress, and sometimes non of the above, it just happens for no real reason. Your dr can advise you best.