I have the worst body shape, I'm an apple. Even when I'm not carrying a bit of stubborn baby weight, my bum and hips are non-existent and usually my waist is bigger. All clothes with a waistband fall down unless I have them muffin top tight.
Tights are the worst. It doesn't matter what size they are, they either have to be uncomfortably tight on the waist or they just slip down so the crotch is round my knees within about 2 minutes. Maternity tights are ace, they pull right up to my boobs and stay up. DD is almost 1 but maybe I'll wear them forever.