You shouldn't always take as gospel what your mother told you. My mother told me that women in the past wrapped their breasts flat with sheeting to stop them bouncing. Well maybe that was they way it was done by her very strict puritan ancestors but now I find that in the 1500's women were wearing a garment that looked very much like a bra, it even looks as though it lifts and separates.
There are some very good articles about this discovery. One at the BBC History Magazine and the other at Medievel Silkwork. If my mother had seen the illustrations on the latters blog she wouldn't have got so confused.