There are surgical procedures that can make your cat unable to reproduce. They involve the removal of ovaries and uterus for female cats; and the removal of the testicles for male cats. Neutering refers to either procedure.
If you have an outdoor cat or multiple indoor cats you should seriously consider having your cat neutered. Unless you are planning on breeding and are confident you will find homes for all the kittens (a female cat can produce up to 15-20 kittens a year), the most responsible thing to do is have your cat neutered.
Benefits of neutering. Even if your cat stays indoors and doesn't live with a viable breeding partner, it's still a good idea to have your cat neutered.
Females. If you have a female cat, spaying makes ovarian cancer impossible and also dramatically reduces the risk of cervical cancer.
It will also eliminate a number of behaviors that you may find undesirable. A female that hasn't been neutered will go into heat around three to four times a year. During this time she may meow constantly or try to get out of the house.
When a female goes into a heat several times without mating she may develop problems like depression, anorexia, diarrhea and vomiting. Neutering will eliminate all such behaviors.
Males. Male cats also benefit greatly from being neutered. It eliminates the risk of testicular cancer and prevents a number of behaviors that can make owning a male cat difficult.
Neutered male cats are far less territorial, will rarely spray urine to mark their territory, and their urine will not smell as strong.
If you have two male cats, neutering them will dramatically reduce the amount they fight. In fact, neutered cats are generally much more docile and easier to handle.
The operation. Preparing for the actual procedure is the same for each gender. You should not feed your cat for about 12 hours before the surgery.
The cat is put under a general anesthetic and hooked up to monitoring equipment to make sure there are no complications. Then an incision is made and the ovaries and uterus are removed in females and the testicles in males. The incision is then closed with stitches that may be hidden inside.
Because a larger incision is needed for a female cat she may need to stay at the clinic for a day or two while male cats generally go home the same day.
Post operation. Your vet may fit your cat with a head cone to prevent the stitches from being chewed. You'll need to keep an eye on the cat to make sure that the wound shows no signs of swelling, tearing, bleeding or discharge. If any of these symptoms appear, inform your vet immediately.
Usually, a cat recovers completely from a neutering operation, and within a week or two the vet will remove the stitches.
During recuperation make sure the cat has plenty of water, clean bedding and a chance to relax in a calming environment.
Side effects. You may notice a small amount of weight gain after neutering and there is a chance of urinary problems occurring. These can be countered if you remember to feed the right cat food. Ask your veterinarian.