Female cats are seasonally polyestrous, which means they may have many periods of heat over the course of a year, the season beginning in January or February and ending in late October. Heat period occur about every two weeks and lasts about 4 to 7 days.[79] Multiple males will be attracted to a female in heat. The males will fight over her, and the victor wins the right to mate. At first, the female will reject the male, but eventually the female will allow the male to mate. The female will give a loud yowl as the male pulls out of her. After mating, the female will wash her vulva thoroughly. If a male attempts to breed with her at this point, the female will attack him. After about 20 to 30 minutes. once the female is finished grooming, the cycle will repeat.[79]
The male cat's penis has a band of about 120-150 backwards-pointing spines, which are about 7 millimeters long.[80] Upon withdrawal of the penis, the spines rake the walls of the female's vagina, which may cause ovulation. Because ovulation is not always triggered by a single mating, females may not be impregnated by the first male with which they mate.[81] Furthermore, cats are superfecund; that is, a female may mate with more than one male when she is in heat, meaning different kittens in a litter may have different fathers.[79]
As domestic cats are not a separate species from their wild relatives, such as the European Wildcat Felis silvestris silvestris, these cat subspecies can all interbreed. This hybridization poses a danger to the survival of the wildcat population, particularly in Scotland and Hungary.[82]
