Final answer:
After the placenta is delivered, the uterus is massaged to control bleeding by stimulating contractions that help shrink the uterus and minimize blood loss.
Step-by-step explanation:
The uterus is massaged after the placenta is delivered in order to control bleeding. This procedure is crucial following the delivery of the placenta to help stimulate contractions that will aid in compressing the blood vessels and minimizing blood loss, which can prevent postpartum hemorrhage. Following birth, the uterus continues to contract to shrink back to its pre-pregnancy size in a process known as involution, further aiding in reducing blood loss and helping abdominal organs return to their pre-pregnancy positions.