This is very interesting to me. I am 37 (Anna, we are the same age!!), and I have-maybe twice weekly- incredible night sweats, and have for a really long time. I have three sisters, and of the two I have spoken to about this, BOTh get them. Now, my older sis, Jenna, is probably in periM, and she is like you guys...20 below, and windows open in the car. My younger sis- Jess, gets warm easily, too. BUT, I freeze all day long...it is just at night. I don't know what my point is, but, to also look at other things besides M. For instance, what do you sleep in? And under what? I MUST have my bedroom windows opened year round. Cats love it, and the utility company loves it, but, nothing like sleeping in clammy clothes...also, caffeine does it to me.....