Arche4life,
I'd imagine it's your weight, which may make it more common in CFers, since many CFers have trouble gaining weight. When I dipped down to 98 pounds, I had at least 3 times that I skipped a period (and actually thought I was preggo). Now that I've had a baby, my weight is remaining steady at 135. Three years ago I was at the 98. What a pendulum.
I'd imagine it's your weight, which may make it more common in CFers, since many CFers have trouble gaining weight. When I dipped down to 98 pounds, I had at least 3 times that I skipped a period (and actually thought I was preggo). Now that I've had a baby, my weight is remaining steady at 135. Three years ago I was at the 98. What a pendulum.