Wow, that must make me ancient, lol! Honestly, I doubt you are seeing hormonal changes at your age, unless you have had kids or are taking birth control pills, something of that nature.
What you may be seeing is muscle development underneath the surface fat, which unfortunately tends to make the dimensions larger, until you lose the fat layer, and the fat that's inside the muscle itself. The fat inside the muscle is like the marbling on an expensive steak, and it adds weight and bulk.
You will need to burn that fat off with lots of aerobics and good diet to see an overall decrease in dimensions. That may very well require more aerobics than the Curves system or your current program provides. You might also want to get your body fat tested, and recheck it every few months. That, along with keeping good records of your hip and thigh measurements, will give you a sense of your progress. Good Luck.
Age 48, 5'6" Living with PCOS.
Start: January 1, 2002, 220 lbs., size 24
Current: 163 lbs, size 10 - 12, 39"-31.5"-39.75"
Goal: size 10 in Levi's 515 jeans.