Spaying is the common term for surgically altering (removal of reproductive function) female dogs and cats. The medical term is ovariohysterectomy. This term indicates that the ovaries and uterus are removed. Neutering is the common term used for surgically altering male cats and dogs. The medical term is orchidectomy signifying that the testicles are surgically removed. Spaying involves entering the pet’s abdomen. It is a more involved surgery than neutering. As long as both testicles are descended in males, the surgery is relatively simple. Retained testicles often required abdominal surgery and post-operative care is similar to that for a spay in these cases. Ace of Spays does not neuter pets with retained testicles.