Do Cats Have Periods? Not Like Humans, but Cats Do Have Cycles

Cats do not have periods in the way humans or some other female mammals do.

Human periods involve shedding the uterine lining when pregnancy does not occur. In cats, however, the reproductive cycle is based on heat cycles, also known as the estrus cycle.

Rather than monthly bleeding, female cats experience repeated heat cycles during their reproductive age, especially in the breeding season — typically early spring to late fall in the northern hemisphere, depending on daylight hours.

When cats go into heat, it marks the most obvious phase of their reproductive cycle. Cats experience heat cycles multiple times a year unless they are spayed or pregnant. A female cat in heat may become overly affectionate, yowl loudly, or attempt to escape the house to find possible mating partners.

Cats are induced ovulators, meaning they don’t release eggs until mating occurs. This trait greatly increases the chances of conception when a female cat mates, which is why unspayed female cats can have many kittens per year, contributing to cat overpopulation if they aren't spayed.

Unlike humans, cats bleed very rarely during their heat cycles. Cats tend not to shed their womb lining like humans do.

If your female cat is bleeding, especially from the genital area, it's not normal and could indicate a medical issue. Contact your vet immediately if you observe bleeding.

Cats can reach sexual maturity and begin their first heat cycle as early as four to six months of age. An unspayed kitten may have her initial cycle prior to being fully grown.

In warmer regions, or when exposed to consistent light, cats may experience heat cycles year-round.

Geographic and environmental factors play a major role. Cats living indoors with artificial light may go into heat more frequently than cats living strictly outdoors.

To avoid unwanted pregnancies and prevent behaviors associated with the heat cycle, it's best to have your female cat spayed sooner rather than later. Spaying provides proven health benefits, reduces behavioral stress, and helps manage the broader issue of stray cat populations.

We created this article in conjunction with AI technology, then made sure it was fact-checked and edited by a HowStuffWorks editor.