When I was diagnosed with perimenopause last year at 41 I was advised that I had to have the NICE guidelines fsh levels greater than 30 along with symptoms of menopause. My symptoms were erratic periods, brain fog, headaches, overwhelming ness, flushes, night sweats, poor sleep, fatigue, abdominal pains etc. In fact I thought I was going mad along with various diseases lol. I had two consistent fsh levels above 30 to trigger hrt treatment. My LH was high, oestrogen was all over and they didn't check progesterone levels.