Spay surgery is formally known as an ovariohysterectomy, which means that your dog's entire reproductive tract, including the ovaries and uterus, are removed from her body. This prevents her from ever having puppies and reduces the risk of certain diseases such as mammary cancer.
Your dog goes under general anesthesia for spay surgery using a tube that runs down her throat and pumps the anesthetic directly into her lungs. The veterinarian makes an incision several inches long that starts just below your dog's belly button and runs toward her tail. This incision is made through both skin and muscle so the veterinarian can access your dog's reproductive tract, which is removed. Two separate layers of stitches are made in the muscles, and the skin is closed with glue, special tape or stitches. The sutures in the muscles will dissolve over time.