Hi - I have pondered recently on the links with how I used to be with Pre Menstrual Syndrome before I had ME/CFS and how I am now (age 57 - periods ended at age 49). I used to have terrible PMS with awful fatigue, and kind of fluey pains in my muscles sometimes. The symptoms seem similar to what I get now with ME/CFS especially the brain fog element and fatigue. It got a lot worse with the peri menopause. I had been on the birth control pill until my 40s when I dropped it as decided I wanted to be invaded by as few chemicals as possible. I did develop an underactive thyroid in my early 40s and the thyroxine did ease some of the general fatigue at this stage, but not pre menstrually. I went to a medical herbalist for treatment for the menopause - had virtually no physical symptoms,(no sweats or flushes) and my periods just got very light and stopped. My symptoms were mostly mental with lots of low mood. Unfortunately for me, ME/CFS has developed entirely post menopause. At the very point in life when i was looking forward to "post menopausal zest" as I think Margaret Mead put it, I have gone down the tube. My 50s have not been what I expected and i feel sad about that but am coming to terms with it.