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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.
Mother cats should be spayed as soon as the kittens are weaned and the mother's milk flow has stopped. ((Kittens are weaned COMPLETELY by the age of 12 weeks old.)) Once the kittens are weaned she can be spayed, at about 8 weeks after giving birth. 8 weeks, but sometimes even earlier.