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While spaying is traditionally recommended for kitties between 4 and 6 months of age, spaying as young as 8 weeks old is considered safe, according to Cat Channel. Many animal shelters actually spay kitties prior to adopting them out at this age.
Most frequently, it is recommended that female kittens be spayed at six months of age, or preferably before their first heat. The surgery, called ovariohysterectomy, involves anesthetizing the animal, and the veterinarian makes an incision through which the cat's ovaries and uterus are removed.