Heat Signs of Cats Unspayed female cats will eventually reach a fertile period in life, which extends well into old age. Hormonal changes that prepare cats for breeding—a process called estrus or oestrus—begins around six to ten months of age. Since cats are efficient reproducers, their estrus, or heat cycle, can occur every 12 to 22 days, at which point she can successfully mate with one or more healthy suitors. Since there's is no easy way to measure a cat's hormone levels at home, changes in her behaviour can be an indicative sign that she, indeed, is in heat. Display of Affection Immediately preceding estrus, your female cat may become unusually affectionate. She may sidle and rub her hindquarters against furniture, stuffed toys, other cats, and maybe even you. You can distinguish this behaviour from pure restlessness (a sign she may be in pain and need to see the vet) by the way she lifts her tail or even occasionally assumes the mating position. Excessive Grooming She may spend excessive time licking her genital area, even though there is no blood present. In fact, contrary to popular belief, a cat in heat should not bleed. Unlike humans, cats do not shed the lining of their uterus during their cycle. However, genital licking can also be a symptom of a urinary tract disorder, which can be serious if not treated promptly. If your cat exhibits only this behaviour without any of the other signs of heat, a trip to the vet is in order. Mating Call and Position Your queen will vocalize loudly. This "calling" may go on for several days unless she mates. She will then assume the mating position: head down, forelegs bent, rear quarters raised to expose the perineum, and tail raised and held to the side of the body. This posture is called lordosis. And when she assumes it, her rear legs will tread rhythmically as if walking in place. Marking Her Territory A cat in heat, similar to a male cat, may spray vertical surfaces with urine. To do so, she will back up to her surface of choice, raise her quivering tail, and may even perform the rhythmic treading described above. To the untrained eye, this looks like a sign of distress. Don't be alarmed, as this is normal behaviour for a cat in heat (although a nuisance to you if you value your furniture). Loss of Appetite Your cat may exhibit a noticeable decrease in appetite. Frankly, her mind is on other things. Pure instinct shifts her bodily need towards reproducing, rather than feeding herself. But monitor her appetite, as this behaviour should last no more than two weeks. Something else may be off if she doesn't return to her normal eating pattern after that time, Need to Escape When in heat, instinct—again—drives your cat to pounce towards the door when it opens. Outside is where potential suitors lie and her need to attract and mate with them becomes apparent. During this time, it is not unlikely for an indoor cat to run away for more than one day and up to a week, or more. Make sure to seal all escape routes and watch her carefully. You may even want to distract her with play to divert her mind from the task at hand.