A nursing bra is a specialized brassiere that provides additional support to women who are lactating and permits comfortable breastfeeding without the need to remove the bra. This is accomplished by specially designed bra cups that include flaps which can be opened with one hand to expose the nipple. The flap is usually held closed with a simple clasp or hook.

An underwire bra is a brassiere that utilizes a thin, semi-circular strip of rigid material fitted inside the brassiere fabric to help lift, separate, shape, and support a woman's breasts. The wire may be made of metal, plastic, or resin. It is sewn into the bra fabric and under each cup, from the center gore to under the wearer's armpit. Many different brassiere designs incorporate an underwire, including shelf bras, demi bras, nursing bras, and bras built into other articles of clothing, such as tank tops, dresses and swimsuits.