Wow, Mark! This certainly makes a lot of sense. This might explain why (at least anecdotaly) the super athletic girls seem to be more prone to PCS.

Pre-injury my daughter exercised to the point that her periods were irregular and her cycles have certainly changed since her injury. She's doing really well now, but I do wonder if some kind of hormone boosting therapy might have helped speed things along. I asked our doc about this early on and her reply was, "I think Mom is our biggest problem at this point". She felt that request was just me being paranoid. The only test she agreed to was thyroid and that was just because we have a family history.

As for saliva vs. blood I am wondering if the saliva allows docs to measure changes in hormone levels over the course of time, where a blood test is a point in time measure? I'm not sure.