A female cat that has been neutered for a long time and keeps meowing may be a sign that it is in heat again. The female cat's follicles will be removed during sterilization. If the follicles are mixed with the blood and drip into the body's fat during the operation, the female cat's body will have to wait until the egg cells are restored. It will grow again and turn into follicles, which will start to secrete hormones and cause the female cat to go into estrus. It is recommended that the owner take the female cat to the pet hospital for examination.