This is a bit of a cry for help about knickers.
I am 37 and have never had a pair of knickers that fit me properly - well not since puberty. I was recently inspired by Caitlin Moran's How to be a Woman to go out and get some decent fitted underwear.
Everything that I ever buy causes wedgies. I have thrown yet more money down the drain recently on new attempts at solving the problem which all cause wedgies.
I don't really have a freaky bum. I am a size 14 in trousers and have to try them on but half will fit no problem. My bum is longer than average. I have big hips. But it's not an odd bum. Even teenagers wouldn't add exclamation marks to any adjectives about it. Needless to say size 14 doesn't work. I have gone up in sizes and today the size 20 arrived! Surprisingly it isn't hanging off my waist but it is a bit saggy at the bottom and the thigh bits are too loose and yet there is still not enough length in them to stop wedgies when I bend over. 
I decided in the end to get a pair of bespoke knickers so I could have one pair that fit me - for special occasions! I can't even find a company that make made to measure knickers only bras.
Am I alone in thinking that asking about waist and hip circumference when sizing pants is clearly an inadequate data set. Marks and Spencers - hear me cry - why don't pants have cup sizes like bras? Imagine if all bras were a b sized cup - it just wouldn't work.
Am I the only woman who has never managed to solve this problem?
Any advice will be really gratefully received. Thanks in advance. 