Q: Can a cat get pregnant if she isn’t in heat?
A: No. “Heat” (technical term: estrus) is the period in which the female cat will allow males to mate with her.
In the Northern Hemisphere, as the days get longer in late January and early February, female cats begin to cycle and come into heat approximately every two weeks. This usually continues in cats until late September. In October, November and December, cats tend to stop cycling until the new season resumes again in late January.
Heat varies in length, between 5 days to 3 weeks. If the female does not mate with a male during the heat cycle, she will experience repeated cycles every 12 to 22 days.
The signs that a cat is in heat include excessive vocalization, becoming very affectionate, rubbing her head and neck against people and objects, rolling and squirming, assuming the mating posture (the rump in the air, tail deflected to the side, back arched downward) and making “treading” movements with her back legs. Some cats exhibit what is called “silent heat.” The cats are in heat, they develop follicles on their ovaries and are fertile, but they show no behavioral signs of being in heat. These cats will allow a male to mate with them. Silent heat is more commonly seen in cats who are lower down in the social hierarchy. If your cat is pregnant, but you never saw signs of heat, she likely was experiencing a silent heat.