I think that can vary from cat to cat, but as a general rule of thumb - they can last from several days to two weeks or longer and repeat every two to three weeks. So, in essence you could have a cat that seems to be in non-stop heat.
No one knows for sure, but there are theories that a cat in heat is pretty uncomfortable overall, so if you are not breeding her, the best thing to do is to get her spayed soon. Not to mention the health issues that can crop up over time with unsprayed cats.
Usually, each active calling period lasts about a week-10 days. But cats aren't consistent at all about that, or about how quickly they'll go back into calling heat. They might only have a break of 3 days, or will wait another month, or, in the winter, might have a break of 3 months, or anything in between. You just never know. Cats are induced ovulators so the only sure way to get them out of heat is if they mate (or are spayed, of course).
Have her spayed ASAP! Living with a cat in heat could make anyone crazy!
Thanks guys! Shybaby has an appointment on April 2. She seems to have been in heat since about March 14 or so? She doesn’t call she is just being friendlier and more visible. Not sure if you have seen my other threads that were called Shyboy before I recently discovered he was a she becAuse she was strutting with her tail up and I could finally see. She has been a tough one to crack but the heat cycle seems to have helped with her socialization. I can stroke her back sometimes now and loves to rub against my legs and or me if I am sitting on the floor. She is still skittish and will occasionally swipe at me with her paw when I am not expecting it when we are interacting. I think she is trying to remind me she is the boss and still in control.
Cats are stimulated ovulators. So essentially they can be in heat until they get some "action". Fortunately that can be faked with a q-tip. I personally have never done nor seen it done, so I recommend a chat with your vet if your at your wits end. Vets often charge more for spays when the animal is in heat (more blood, increased surgery time and materials) so I think it'd be worth talking to your vet about to get her out of heat prior to the surgery.