Cat World > Cat Reproductions > Cat in Heat (estrus) - Signs, Duration & Prevention of Cats in Heat

Cat in Heat (estrus) - Signs, Duration & Prevention of Cats in Heat

What is a cat in heat?

Also known as 'estrus cycle or calling' a cat in heat is when the female cat (female cats are also known as queens) is fertile and receptive to mating. Estrus is usually seasonal but also depends on a number of factors including the number of daylight hours, age and general health of the cat.

There are actually four phases to the cat's heat cycle:

  • Proestrus
  • Estrus
  • Metestrus
  • Diestrus

This article will look at the second phase estrus, where the female is receptive to mating.

At what age does estrus begin?

Estrus begins at puberty when this starts varies from cat to cat and breed. Some breeds such as the Siamese can call as early as four or five months. Other breeds may not reach sexual maturity until 10 months or older.

Cat mating season:

Cats tend to be seasonal maters, although they may go into heat and produce a litter at any time of the year. Typically the feline mating season begins in spring when the days start to become longer and runs through until autumn. Cats are polyestrous, which means they will have more than one heat cycle in a year.

What are the signs of estrus in cats?

Signs of estrus include:

Your cat may become extra affectionate towards people and other cats, rubbing against their legs, or weaving in and out between their legs or rolling on the floor.

  • If she is stroked, she may lay her front half low, and raise her hindquarters, treading up and down with her hind feet, and move her tail from side to side. This is known as lordosis.
  • Persistent vocalisation. This is often louder than usual and can be described as a yowl.
  • Licking of the genital region.
  • There may be a clear discharge from her vagina.
  • Loss of appetite.
  • She may spray on vertical surfaces.

Some cats are what is known as silent callers and may display none of the above signs.

If your cat is in heat, keep her indoors. If she is an indoor cat already, be extra careful to keep windows and doors closed because she will be keen to get to a male cat and mate.

How long does a female cat stay in heat?

Estrus typically lasts between 7 to 10 days. If your cat doesn't become pregnant then it will repeat every 14 to 21 days until she does become pregnant or the season's change.

There are three possible outcomes:

  • The cat mates and becomes pregnant.
  • The cat mates, doesn't become pregnant, has a pseudopregnancy (also known as a 'false pregnancy') and comes back into heat 30 or so days later.
  • The cat doesn't mate or become pregnant and comes into heat 14 to 21 days later.

How often does the female cat come into heat?

If the cat doesn't become pregnant during a period of 'heat', she will go out of season for 2 - 3 weeks and then come back into heat. This can continue until the days shorten in autumn (around September in the Northern Hemisphere and March in the Southern Hemisphere).

Can I prevent a cat coming into heat?

The only guaranteed way to prevent a queen from coming into heat is to have her desexed (spayed). Not only will this prevent 'calling' and ensure no unwanted kittens are brought into the world but there are also health benefits to desexing a female cat. Entire cats are at risk of developing cancer of the uterus or ovaries, pyometra, and breast cancer.

Do sibling cats mate?

Yes, brothers and sisters will mate, fathers and daughters, mothers and sons. Cats do not discriminate when it comes to mating.

Is it possible for a litter of kittens to have different fathers?

Yes, cats are induced ovulators, their eggs are released after they have mated and can survive for up to 24 hours. If your cat mates with multiple male cats, then the kittens born can potentially have different fathers.

What should I do if my cat comes into heat?

Keep her indoors and away from any entire (Tom) male cats and book an appointment with your veterinarian as soon as possible.

If she does get out and mate, it is not too late. She can still be desexed. Speak to your veterinarian about this. He may also wish to test for FIV and FeLV if she has mated with an unknown/untested tom.

Should I let my cat mate when she is in season?

Unless you are a registered breeder, and this is a planned mating then no, you should not permit your cat to mate.

There is a huge cat overpopulation problem and breeding your cat just contributes to this. For every kitten you have, which you may pass on to friends or neighbours, that is one kitten in a shelter who could have been rehomed.

Also, unless you have tested the tom (male cat), there is no way you will know if he has either FIV or FeLV, both of which are viruses which are fatal in cats.

Desexing (also known as spaying) can be performed while your cat is in heat, but veterinarians typically prefer to spay a cat who isn't in estrus.

My female cat has been spayed but she is still coming into heat:

This sometimes happens in spayed cats if there are any remnants of the ovaries left behind during her spaying operation. This tiny portion of the ovary continues to produce hormones which trigger the estrus cycle in the cat. It is not possible for her to become pregnant, however.

What are the signs of pregnancy in cats?

The first sign of pregnancy is pinking-up, where the nipples become pinker and slightly swollen. This happens around the third week of pregnancy.

Weight gain occurs around the fourth week of pregnancy.

My cat is already pregnant, how long does pregnancy last in cats?

A cat is pregnant for approximately 63 days.

How many kittens are in a litter?

This depends. First-time mothers may have a small litter of one or two. The average number of kittens in a litter is approximately 4 - 6.