Spaying and Neutering Cats: When and Why

Quick answer

Spaying (females) and neutering or castration (males) stop cats breeding and cut down on spraying, roaming and fighting. They also protect against several serious health problems. Many vets and cat welfare groups now recommend doing it at around four months old, before a kitten can get pregnant or start spraying, although some vets still prefer five to six months. The surgery is routine and most cats are back to normal within days.

What the operations involve

Spaying removes a female cat's ovaries and usually the uterus, through a small cut on the side or the belly. Cats are back on their feet the same day, but the wound needs about 10 to 14 days to heal.

Castration removes a male cat's testicles through two tiny cuts in the scrotum. It's quicker and recovery is faster, often a couple of days.

Both are done under general anaesthetic. Most cats go home the same day.

Why neuter at all

Preventing unwanted kittens

Cats breed fast. A female can come into season as young as about four months, and unspayed females come back into season every few weeks during the breeding months until they're mated. A cat can have several litters a year. Shelters around the world are full of kittens from "just one accident".

Health benefits for females

• Mammary (breast) cancer: these tumours are common in unspayed female cats and are usually malignant. Spaying early, ideally before the first season, greatly lowers the risk.
• Pyometra: a life-threatening infection of the uterus that can't happen after spaying.
• No pregnancy or birth complications, and no repeated seasons, which are stressful for the cat (and noisy for the household: calling, rolling, restlessness and trying to get outside).

Health and behaviour benefits for males

Unneutered tomcats roam widely to find mates, fight other males and get injured on roads. Fighting spreads diseases like feline immunodeficiency virus (FIV) through bite wounds, and abscesses from bites are common. Intact males also spray strong-smelling urine to mark territory, often indoors. Neutering reduces all of this, and the smell of a tomcat's urine fades.

Females spray too, especially when in season, and spaying usually helps.

The four-month question

For years, six months was the standard age. Organisations including International Cat Care and Cats Protection now recommend around four months instead. The reasoning is simple: kittens can become sexually mature at about four months, so waiting until six leaves a window for pregnancies. Studies in kittens neutered early haven't found the developmental or behaviour problems people once worried about, and the surgery in young kittens tends to be quick with fast recovery.

Practice still varies between countries and individual vets. Some prefer to wait until five or six months, or until a kitten reaches a certain weight. Both approaches are reasonable. What matters most is getting it done before your kitten has the chance to breed. Talk about timing at your kitten's vaccination visits (see the kitten vaccination schedule) and keep young females indoors until they're spayed.

Myths worth clearing up

"She should have one litter first." No benefit to the cat at all, and it raises her cancer risk.

"Neutering changes their personality." Your cat stays your cat. What changes is the hormone-driven stuff: calling, spraying, roaming and fighting.

"Neutered cats get fat and lazy." Their energy needs drop by a meaningful amount after surgery, so the same portions lead to weight gain. Feed for the cat in front of you, not the old amount.

"Indoor cats don't need it." An indoor female in season will cry, try to escape and may spray. An intact indoor male will usually spray. Neutering makes indoor life calmer for everyone.

"It's too late for my adult cat." Healthy adults can be neutered at any age.

Before the operation

• Your vet will check your cat is healthy. Older cats may have a blood test first.
• You'll usually be asked to take food away the night before. Follow your vet's instructions exactly, as they differ for young kittens, which shouldn't go long without food.
• Keep your cat indoors the night before so it doesn't wander off before surgery.

Aftercare at home

Most cats are a bit sleepy and wobbly the evening after surgery.

• Keep them indoors and somewhere quiet and warm for the first night.
• Offer a small meal that evening if your vet says so, then normal food the next day.
• Limit jumping and rough play for about a week, longer for spayed females if your vet advises.
• Check the wound daily. A little redness is normal. Swelling, discharge, a gaping wound or bleeding are not.
• Stop licking. Your vet may provide a cone collar or a soft body suit. Licking can open stitches or cause infection.
• Use paper litter or shredded newspaper for a few days after castration, if your vet recommends it, to keep dust out of the wound.
• Give pain relief only as prescribed. Never give human painkillers; several are toxic to cats.
• Go back for the post-op check and stitch removal if needed.

Call your vet if your cat isn't eating by the day after surgery, seems very flat, is in obvious pain, or if the wound looks wrong.

Adjusting food after neutering

Weigh your cat before the operation and every few weeks after. Cut portions slightly if the weight creeps up, and keep up daily play sessions. If you feed a kitten food, your vet can tell you when to switch to an adult diet. For general feeding and routine, see the cat care guide for beginners.

Neutering laws and rules for selling or rehoming cats vary by country, so check what applies where you live. If you're looking for a kitten, ask the seller about vaccinations and neutering plans, and browse cats on Paalo to compare verified listings.