In many cases, when you purchase a Maine Coon kitten from a breeder or a shelter, you will be required to sign an agreement. That agreement may cover a great deal of territory, but one area is almost always covered - spaying and neutering. The breeder or shelter may require that you have the cat altered by the time it reaches a certain age.
Kittens can be spayed after they have reached four months of age, but your veterinarian may prefer to wait until it is six months old. Many Maine Coon breeders do their own spaying and neutering, before the kitten is adopted, and often suggest spaying and neutering at around fourteen weeks of age.
The reason that veterinarians have postponed neutering and spaying is that anesthesia is used, and in the past, using anesthesia on kittens was tricky. Today, there has been a great deal more research done on this and the practice has been perfected - enabling veterinarians and breeders to spay kittens earlier in life.
This practice cuts down on the possibility of someone adopting a kitten, and failing to get it spayed or neutered later. Maine Coon breeders worry about this especially, since they want the breed kept pure, and they do not want any unplanned litters. This is also an effort to prevent inbreeding between siblings at an early age. This is the only benefit of early neutering.
There are those who object strongly to EAA, or Early Age Altering. These veterinarians and associations believe that EAA leads to an increased risk of fracture to long bones, obesity, a negative effect on overall growth, changes in behavior, and an increase in disease risk. They also feel that using anesthesia on kittens is too risky.
Spaying and neutering overall is not cruel to the animal, and they actually experience minimal pain. In most cases, they only experience mild soreness for a day or two. Spaying is usually more expensive than neutering. In case you are not aware - and many people are not - females are spayed, and males are neutered.
If you want to breed your Maine Coon kitten at some point, this is something that you will need to discuss with the breeder - often before the kitten is even conceived. The breeder generally charges a much higher fee when breeding rights are given to the new owner. Note, however, that only kittens that come from titled parents have any real monetary value. So, if your kitten doesn't have titled parents himself, you need to look for a litter that does come from titled parents.
Unless you plan to breed your Maine Coon, it definitely needs to be altered. Otherwise, a male will constantly be 'spraying' to mark his territory and a female will keep you up days and nights when she goes into heat. Also note that when you enter shows with your Maine Coon, you must specify that the animal has been altered, and he or she will enter class divisions specifically for altered Maine Coons.