I've been in menopause for 2 years and been on HRT since. I gained 5 lbs and then lost it after going on Cymbalta, which curbs my emotional eating. I'm average in size (5'8", size 8).
fwiw, my mother hasn't gained a pound -- her belly is a little soft at 80, but she's always been very thin at 5'10" and something like 125 lbs.