When Can I Have a Chihuahua Neutered?

Neutering is controversial and actually not necessary for healthy dogs.

Early neutering, as was often the case in the past, is only carried out in exceptional cases, e.g. if two Chihuahuas of different genders live in a household and no offspring are to be produced.
In the case of male and female dogs, sexual maturity is usually awaited before castration is considered. In the case of female Chihuahuas, the intervention is therefore carried out at the earliest after the first heat.

Let a veterinarian advise you if and when the surgery makes sense for your Chihuahua. Another alternative is chemical castration.