Becoming an adult: Kitten puberty and heat cycles explained

Disclaimer: This article, its content, and its related references do not constitute veterinary advice and should not be considered a substitute for veterinary care. If your pet is showing any symptoms that could indicate a medical emergency, please seek immediate emergency care.

Cats enter puberty and reach sexual maturity at around four to six months of age. Physical and behavioral changes occur as sex hormones are released and the cat is ready to reproduce. Physical and behavioral signs of puberty, such as coming into heat, urine spraying, and unwanted litters of kittens, can be avoided by spaying or neutering your kitten when recommended by a veterinarian. If you have a kitten, read on to learn about:

• When kittens go into puberty
• Signs of puberty and heat in kittens
• How to avoid or minimize unwanted behaviors associated with puberty

There are five cat life stages as defined by the American Animal Hospital Association (AAHA):

• Kitten: Birth to one year
• Young adult: One to six years
• Mature adult: Six to ten years
• Senior: Over ten years of age
• End of life: Varies between individuals

Kittens reach sexual maturity and are capable of reproducing before they’re fully grown. Cats aren’t considered socially mature until around one year of age.

When do kittens go through puberty?

Puberty in kittens typically begins between four and six months of age. Timing can vary between breeds and individuals, though shorthair cats often reach puberty before long-haired breeds.

Female kittens go into heat for the first time at around four to five months of age. If they remain intact, a female cat usually comes into heat every few weeks if they’re not bred or do not become pregnant. An intact female cat that has gone through puberty is called a queen.

It isn’t always obvious when a male kitten starts to go through puberty, since they don’t have heat cycles, but once they’ve gone through puberty, they remain ready to reproduce any time a female in heat is available. An unneutered male cat that has gone through puberty is called a tom.

When the production of sex hormones changes during puberty, physical and behavioral changes occur. These changes include:

• Urine spraying or territorial marking (especially toms)
• Unusually strong urine odor (toms)
• More interest in humping or sexual behaviors
• Attempts to escape or roam to mate
• Starting to go into heat (queens)

These behaviors can be disruptive to cat owners. The sudden onset and intensity with which a kitten in heat vocalizes and rolls around can be alarming, leading you to think they’re injured. In addition, cats attempting to escape to roam or mate can result in injuries. Intact males often fight, and roaming cats are more likely to be injured by cars, other cats, and wildlife. Intact cats who roam are also at much higher risk for exposure to feline immunodeficiency virus (FIV).

The onset of puberty in female cats (queens) is typically marked when they go into heat for the first time. This indicates they are physically ready to breed and capable of reproducing, even though they’re neither physically nor socially mature.

Heat (estrus) is part of the estrous cycle, a female cat’s reproductive cycle. There are five stages of a queen’s estrous cycle:

• Proestrus: The body prepares for estrus, or heat
• Estrus (heat): Queens allow males (toms) to mate with them
• Interestrus: The period of time after estrus before a new cycle of proestrus if the queen has not mated
• Metestrus: The start of pregnancy if a queen becomes pregnant
• Anestrus: The period of reproductive inactivity where the cat does not have heat cycles

The feline reproductive cycle repeats every three to four weeks until a cat is bred. A cycle lasts between four and seven days. Females usually have their first heat at around six months of age, but this can vary between four and 12 months.

Cats are traditionally considered to be seasonally polyestrous, meaning they have multiple estrous cycles during a specific season of the year, influenced by the length of daylight hours and other factors. This may be followed by a period of reproductive inactivity, or anestrus. However, indoor cats and cats in warm environments may cycle year-round.

In the northern hemisphere, breeding season typically occurs between January and October. “Cats who do not become pregnant typically continue to go into heat every three to four weeks indefinitely,” explains Dr. Jo Myers, a veterinarian on the Vetster platform. “It can seem as if they start a new heat cycle as soon as the previous one fades away.”

The heat cycle in cats is only broken if they are getting bred, become pregnant, or get spayed. Cats who have the opportunity to breed will typically have three to five litters of kittens a year.

Signs of heat in cats

Apart from attracting male cats and allowing them to mate, cats in heat often appear to be distressed or injured, showing signs such as:

• Unusual postures, like arching the back and raising the rear quarters, moving the tail to one side
• Excessively rubbing against objects and/or rolling around
• Vocalization
• Tremors or rigidity in the body and tail
• Responding to being touched by batting, scratching, or running away
• Vaginal discharge
• Treading with the hind legs while standing
• Attempting to escape

Cats often do not have much vaginal discharge during heat, so this sign can be easily overlooked by pet parents. Treading with the back feet should not be confused with “making biscuits” with the front paws, a behavior that both intact and sterilized cats can do. Behavioral signs of heat can vary between individuals, and not all cats exhibit all of these signs.

While the behaviors shown by pubescent kittens are normal and not distressing for them, they can be surprising, frustrating, or even alarming for pet parents. Understanding that these are instinctive, hormonally driven behaviors can help you respond with patience and compassion. If you’re feeling overwhelmed, you’re not alone — many cat owners find this phase difficult to manage. The easiest way to minimize the difficulties associated with puberty is to avoid it entirely by spaying or neutering your cat before puberty begins. If you’re unsure what’s normal or how best to help your kitten, your veterinarian can provide guidance tailored to your pet’s age, behavior, and overall health.

Many kittens who are adopted from shelters are already spayed or neutered by the time they leave the shelter. If your kitten is not spayed or neutered, or if you’re unsure whether or not they are, talk to a veterinarian. If you and your veterinarian have decided not to sterilize your kitten, you can try to minimize the difficulties associated with reproductively active cats by:

• Housing tomcats where territorial marking is not a problem
• Ignoring the vocalizations and behaviors from a female cat in heat or moving them to where they are less likely to be bothersome
• Providing plenty of exercise and mental stimulation
• Keeping cats indoors
• Separating male and female cats, even if they are littermates or bonded (these relationships do not prevent mating)

Talk to a veterinarian if:

• Your cat has a lot of vaginal discharge (more than they can keep clean)
• Signs of illness accompany signs of heat
• Your unspayed (intact) cat does not have their first heat by 12 months of age
• Your spayed cat shows signs of heat

When should kittens be spayed or neutered?

There is no one-size-fits-all approach when determining the right time to spay or neuter a kitten. The optimal age depends on many factors. It’s generally recommended that kittens are spayed or neutered at around five months of age, before they reach breeding age or come into heat for the first time. This is to prevent unwanted pregnancies and certain health conditions, including:

• Uterine infection (pyometra) or cancer
• Mammary gland tumors
• Testicular cancer
• Ovarian tumors
• Persistent heat
• Injuries associated with roaming, such as fights with other cats

Spaying and neutering before sexual maturity may also help prevent unwanted behaviors, such as:

• Urine spraying
• Certain types of aggressive behavior
• Humping
• Vocalization around the home
• Attempting to escape

Factors such as a kitten’s size, body condition, and underlying health issues can influence the right time to have them spayed or neutered. You can talk to a veterinarian during an online virtual care appointment about the best time to spay or neuter your young feline friend or to get advice on how to manage signs of puberty.

How do I know if my kitten is going through puberty?

Notable signs of puberty in cats include urine spraying or marking territory, increasing attempts to escape or roam, and coming into heat for female kittens. A kitten in heat typically spends a lot of time vocalizing, rolling around, and arching its back. It’s harder to tell when a male kitten reaches puberty, but they typically show more interest in female cats in heat and develop particularly strong-smelling urine. Kittens often reach puberty around the age of five months, but this can vary between four and 12 months of age.

At what age do kittens go into heat?

Female kittens reach sexual maturity and go into heat for the first time around the age of five months, but this can vary between four months and a year old. Once a female kitten comes into heat, they’ll continue to cycle in and out of heat every few weeks until they get bred, become pregnant, or are spayed. Male cats do not go through heat but may exhibit other signs of puberty, such as attempting to escape and roam, humping, and marking territory.

How do cats act during puberty?

Cats may exhibit unwanted behaviors once they reach puberty, such as marking territory (urine spraying), aggressive behaviors, and attempting to escape in order to roam and breed. Female cats in heat typically spend a lot of time rolling around on the floor, vocalizing, and walking around in unusual postures with their backs arched and tails off to one side. These changes can make it appear as though the cat is injured or in distress, but these are normal, hormone-driven behaviors.