The boyish silhouette of the 1920s required special undergarments. Generally, a bandeau was used to flatten the bust with a single piece of fabric. Corsets and girdles were still heavily boned. Corset substitutes were made of softer elastic and referred to as “step-ins.” Specialty corsets were created for wear during sports, dancing, and even pregnancy. Towards the end of the decade, as a natural shape became more popular, brassieres with cups and mild shaping were developed.
Loose-fitting bloomers or knickers were made of silk or rayon and were gathered just above the knee. They came in a number of forms including one-piece camiknickers, teddy’s, step-ins, or just plain drawers (which resembled slightly flared, bifurcated skirts). During the early years of the 1920s, calf-length petticoats were worn, but as hemlines rose, these garments were rendered obsolete.