Hi Mike,

There is no easy answer as these things can vary from cat to cat. A cat can be in heat a few days to a week, and this can occur once, twice, or even 3 times or more per year. Some unspayed cats, especially if they develop ovarian cysts, can seem to go in and out of heat almost constantly. Unfortunately with every heat cycle a cat goes through they are more likely to develop mammary cancer.

Regards,
PHKitkat