An early age Spaying/Neutering of cats
The authors of the next 2 articles studied long-term effects of pediatric gonadectomy and concluded that gonadectomy can be safely performed in cats under 6 months of age. These articles are followed by reports of 2 studies of cats neutered at over or under 24 weeks of age. The authors found no increased risk of disease or other health problems in cats neutered early.
Studied 1,660 cats adopted from shelters
Early-age gonadectomy beneficial in male cats
Asthma, gingivitis decreased in both sexes
Gonadectomy safe in cats under 6 months of age
Results of that study also suggest that prepubertal gonadectomy may result in some unidentified protective effect on the urinary tract, compared with traditional-age gonadectomy in some cats.
Long-term outcome of gonadectomy performed at an early age or traditional age in cats. (PDF, 270 KB)
Health status of cats monitored for 3 years
No increase in physical or behavioral problems
No increase in infectious disease in either group
Early-age neutering did not increase problems
All this information was taken from American Veterinary Medical Association’s website.