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The normal reproductive cycle of the queen is very different from the bitch. Unlike the bitch, the queen is an induced or reflex ovulator and is seasonally polyestrous, having more than one estrous cycle during the breeding season (Houpt 2005). Queens only ovulate in response to cervical stimulation. The queen’s cycle consists of four phases that include proestrus, estrus, metestrus (diestrus and interestrus), and anestrus (Griffin 2001). Metestrus is the time between two estrus cycles if breeding has not occurred. If breeding does not occur, the queen may return to proestrus with the next follicular wave, which is typically between one to three weeks but has been reported from three days to seven weeks in some cases (Feldman and Nelson 1996; Root et al. 1995). Anestrus is the time between breeding seasons. The age kittens begin to cycle is dependent on when they were born relative to the breeding season, typically anywhere from 6 to 10 months.

The female will undergo several behavioral changes during the estrus cycle. During the proestrus stage, the queen is often very affectionate, rubbing her head on any object, both animate and inanimate, and seeming friendlier, although some females will not show any signs during proestrus. This behavior is consistent with scent marking to notify other cats that there is a female coming into estrus. There may be a slight increase in vocalization and rolling, as well as stretching and lying in lateral recumbency while kneading with the paws. Toms may show some interest in the queen at this time, although she will not be interested in them and may act very aggressively: slapping, hissing, chasing, and/or biting the tom. The vulva may be slightly enlarged, but this generally goes unnoticed because of its anatomical location and relatively small size to begin with. Additionally, there may also be a discharge; this is not commonly observed due to the fastidious grooming behavior of most cats. However, one might notice that the queen is grooming her perineal area more often.

Estrus is the period in which the female is receptive (allows copulatory mounting) to the male. The queen often vocalizes loudly and constantly during this phase; indoor queens may run from window to window while vocalizing. The estrus queen may roll more vigorously. During petting, she will often lower her chest and raise her pelvis. She may also tread with her back legs and deviate her tail to the side. Excessive and persistent vocalization is alarming to some, and those unfamiliar with normal feline reproductive behavior may believe the cat is ill or in severe pain. The estrus queen also urinates more often, a sign that mimics a UTI, and may spray urine as well (Beaver 2003). Her excessive activity may result in decreased appetite and resultant weight loss. The proestrus and estrus stage can last anywhere from 9 to 10 days if the queen remains unbred and approximately 4 days if bred (Banks 1986; Root et al. 1995; Houpt 2005).

The length of metestrus varies from one to two days to several months, averaging seven to nine days for a non‐bred queen (Banks 1986). If a queen is bred, she will generally return to estrus approximately one to two weeks after weaning during the breeding season, otherwise she will cycle again the next season. There have been reports of bred queens coming into estrus while pregnant. If the queen is bred during the pregnant estrus cycle, the resultant kittens will be immature. When she gives birth, there will be both full‐term and immature kittens; this is known as superfetation (Hunt 1919). Some lactating queens will come into estrus 7 to 10 days after parturition (Schmidt 1985).

Feline breeding may be described as a violent act. The male and female call back and forth to each other. Multiple males fight, while the female watches at a distance. Once the female has decided on a mate, she allows him to mount, and he bites the back of her neck. The queen emits a piercing howl, which is thought to be the result of the spines on the male penis contacting the cervix after ejaculation (Banks 1986). After the cry, the queen almost immediately jumps away and actively rejects the male. This may include hissing, spitting, and striking at him. She then rolls, stretches, and vigorously grooms her vulva. The time between copulations is variable, from 20 minutes to several hours, and is determined by the queen.

A pregnant queen initially does not display many physical or behavioral changes compared to an anestrus cat. During the last three weeks of gestation, the physiological changes typical of pregnant animals begin to occur, including distension of the abdomen as well as reddening and slight swelling of the nipples. Because of the enlarged abdomen and change in center of gravity, the queen may not be as agile and therefore may not jump up as much. The enlarging uterus puts pressure on the internal organs. This results in the queen preferring small, frequent meals. She may also demonstrate increased frequency of urination and possible difficulty having bowel movements. The increased pressure and discomfort may result in increased grooming of painful areas.

The gestation lasts between 63 and 65 days on average. Since the queen breeds multiple times and is an induced ovulator, it is difficult to know the exact day of conception. Many queens become more docile and may nest build as they get closer to parturition. Nest building by queens is not reported to be as destructive as the same behavior by bitches. They tend to seek closets and other dark, secluded areas. Unlike dogs, a drop in rectal temperature is not a reliable predictor of impending parturition. Milk and colostrum may be present up to a week prior to parturition. Many queens become less active as their discomfort level increases, but some may seem more agitated or restless as they search for a place to deliver.

Queens in a colony setting will often cooperatively raise and nurse the kittens. In a shelter situation, this may be helpful, as a queen with a recent litter may willingly foster other kittens. Cooperatively nursed kittens grow faster and are weaned sooner, and, consequently, the queens return to estrus sooner than non‐cooperatively nursing queens. If free to do so, queens will move kittens approximately every three weeks. This is not due to fouling of the nest but is thought to be a way to hide from predators. This suggests that if a queen with kittens in a shelter setting is unable to hide her kittens as she wishes, she may experience some degree of stress. Placement in a foster home, if possible, may be best for the welfare of the queen and kittens. When this is not an option, a quiet and secluded location in the shelter should be identified. Stress from a variety of different causes has been demonstrated to cause permanent changes in the neurophysiological development of offspring, and this can have far‐reaching effects on the suitability of kittens as pets.

Anestrus in the queen is usually seasonal, although one study reported that only 90% of the longhaired queens and 40% of the shorthaired queens in the study population entered anestrus (Jemmett and Evans 1977). Therefore, it would not be uncommon for a female cat to exhibit estrus‐type behavior year‐round.