The Depression brought conservatism, and women in the 1930s returned to the curvy silhouette of eras past, with lingerie returning the emphasis to hips and bust [ which depending on your opinion,wasn't such a bad thing].
Pointed rigid bras came next that maintained their shape. Then came "falsies" ,pads worn inside the bra that were designed to enhance the fullness of the bust,which became the push-up bra, stiffened cups supported by underwiring.