Here's why:
* Cats reach sexual maturity at around 4-6 months old.
* They can cycle through heat periods multiple times a year, particularly during spring and fall when the days are longer.
* Age doesn't prevent a cat from going into heat. While some cats may become less fertile as they age, they can still go through heat cycles.
If your cat is unspayed, going into heat can be a sign of her reproductive cycle and she may be looking for a mate. It's important to consult with your veterinarian about the best course of action for your cat's health and well-being.