This calibrated under-buttock drape folds out into a large sterile surface for delivery. The device allows for blood to be swept into a large calibrated pouch that indicates when the danger points have been reached (500 mL is the official definition for a postpartum hemorrhage). The obstetric drape comes in sterile packaging and folds out to a 1x1 meter sterile area for a woman to give birth. At the bottom of the sterile area is a pouch that holds more than 2500 mL of fluid, allowing for accurate measurement of postpartum blood loss. The pouch itself also includes a flexible plastic filter to ‘catch’ material that is not liquid.