By Jennifer Copley (Last Updated 12 May 2011)
Just before going into heat, many female cats become more affectionate than usual. While in heat, they are inclined to yowl, lick their genitals frequently, roll around on the floor, and assume a mating position (head down, hindquarters raised, tail held out of the way). Usually only male cats spray to mark territory, but unspayed females may also spray when in heat.
Female cats in heat are extremely anxious and frustrated when confined indoors. Even those that are usually content as indoor cats are likely to make desperate escape attempts while in heat.
How often do unspayed female cats go into heat?
Unspayed female cats go into heat every 14-21 days (until they become pregnant) and this phase can last anywhere from 3-16 days.
Can a pregnant cat go into heat?
Some cats go into heat and mate when already pregnant. This phenomenon is known as superfetation when it results in a queen carrying two litters, one more advanced than the other. The younger kittens may be born alongside their more developed siblings, in which case they usually die. However, they may also hang on and be born on their due date, which can place a strain on the nursing mother, who suddenly has to cope with even more kittens.
See the Pregnant Cats and Kittens Page for information on caring for pregnant cats, kitten development week by week, kitten training, kitten care, and more. For a full list of cat articles, see the main Cats page.
- Morris, Desmond. (1987). Catlore. London: Jonathan Cape Ltd.
- Nash, H. (2009). “Spaying (Ovariohysterectomy): The Benefits in Cats.” PetEducation.com.