The removal of the gonads (ovaries) is popularly called sterilization, but the actual name is castration. During sterilization, the glands are not removed but tied off.
Researchers claim that the life expectancy of a neutered cat is twice as long as that of a fertile animal (Kraft, Dankert: Development of life span in a cat population, Kleintierpraxis 1997). This, however, is mostly explained by the fact that neutered cats that walk freely outside stay closer to home. The “open” cats often go further away on research, which significantly increases the risk of a traffic accident.
Moreover, domination battles (and the associated infection risks) also play an essential role. What is certain, in any case, is that a castrated cat is calmer in the house and more people-oriented. Also, a neutered cat dramatically reduces or eliminates the risk of uterine inflammation, cysts on the ovaries, and mammary gland tumors.