During pregnancy, a woman’s body goes through many changes, including an increase in blood volume and fluid; this fluid can remain in the interstitial spaces of the tissues, which may cause swelling, often in the legs, ankles and feet. Worn during the day, maternity compression stockings counteract swelling and protect against varicose veins by applying a light, soothing pressure to the exterior portion of the legs, which helps prevent fluid from accumulating.