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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.
Best Answer: Most vets who have bothered staying informed with current research will now spay a female kitten once they've reached the 2 pound mark, or 8 weeks. Many prefer that females be a bit larger - say, 2 1/2 to 3 pounds, and this would make them about 12 weeks old.