Cats do not menstruate, only humans and primates have menstruation as a condition. Cats are different from dogs in that dogs bleed from their vagina when they are in heat, but cats do not. Cats will only have a small amount of clear mucus coming out of their vagina, and they are seasonal animals that come into heat several times, lasting around 3-10 days each time. When a cat has a bleeding vagina, the owner should immediately take the cat to the animal hospital for examination and treatment, this may be a sign that the cat is ill.
