Hi! I know I have read quite a bit about people not having a period for months on end...but no one ever mentions what the causes of this might be other than pregnancy. I have not had a period since July....and have taken pregnancy tests, which confirmed what I thought...that I was not pregnant. I am wondering what other things maybe going on in my body to cause me not to have a period. I only exercise 3-5 times a week, 30 minutes at a time, so not excessively. I am not stressed out at work or at home. What types of tests (lab work) might I need to have done to determine what might be causing my absent period?