Social pressures and increasing veterinary costs are contributory factors. However, the largest single cause is irresponsible breeding. Female cats can reproduce under six months of age. Unneutered females can become pregnant up to three times per year and produce five-six kittens in every litter.
So why should you get your cats neutered? There are many benefits and minimal risks with simple surgical procedures performed by experienced vets.
Neutered cats are generally happier, healthier, more sociable and much less likely to leave the security of their own home and garden. Unneutered females will come into season frequently throughout the year and attract determined unneutered males from a wide area.
For male cats, the risks of road injuries and fight wounds are significantly higher because they roam over great distances in search of responsive partners.
Unneutered males tend to spray urine to mark territory and that may include spraying inside the home. They are also more exposed to the FIV virus which can be passed from infected animals through saliva entering bite wounds during battles over females. There is currently no effective treatment for this condition.
At a social level, cats which are allowed to reproduce repeatedly are contributing to the national problem of excessive cat population. A single female cat can produce up to 18 kittens per year and all will need suitable homes. There is some risk to the mother during pregnancy and birth.
So it makes sense at all levels to ensure your cats are neutered. Older cats can be neutered at any time (except when a female is already pregnant). The recommended age for neutering kittens is around four to five months.