Female kittens can come into season well before they are a year old. It is therefore advisable to consider neutering at six months of age.
During the breeding season a female cat, which has not been spayed (a queen) will come onto heat every three weeks. When on heat, a female cat is usually extremely vocal and it is not unusual for an inexperienced owner to think their cat is crying in pain. She is usually very affectionate, even more so than normal, and will rub against your legs and furniture. She may also adopt a characteristic position, called “lordosis”. In this stance, she crouches down on her front legs and holds her rear end up, in a position ready to mate.
If you do not want your cat to have kittens, it is advisable to have her spayed.