The question in the title is a roundabout way of asking if female cats have periods. As female cats come into heat in cycles (the estrus cycle) we have to make sure we understand what a human period (cycle) means in terms of menstruation and ask if cats have the same thing.
Women obviously know what a period is but some men might not. If pregnancy does not occur, and except during pregnancy, it is the monthly discharge of blood and mucosal tissue from the lining of the uterus via the vagina. It is discharged because it is not needed as the woman’s egg is not fertilized, her body no longer needs the thicker lining of the uterus, so it starts to break down and is eventually expelled.
Cats don’t do this. They don’t have ‘periods’ as described. They are induced ovulators – the physical act of mating causes the female to ovulate rather than it automatically occurring. Therefore, the answer to the question is that female cats do not ‘bleed’ in this meaning of the term as the egg is fertilised when created.
However, Drs Llera and Yuill at VCA Hospitals write online that uncommonly you might observe feline vaginal bleeding during estrus. I’ve added that bit of information for completeness but it does not change the answer as stated in the paragraph above. Bleeding like this is because of something other than coming into heat in my view and I think it adds confusion to the discussion. There might be a urinary tract infection for instance. As mentioned, cats don’t have periods and therefore don’t bleed when in heat.
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