There is not enough information to prove one way or another. When the piglet is born, the opening to the abdomen is suppose to be closed. The theory is that there may be an incomplete closure, and it doesn't close until 4-5 months of age. If the pig is neutered, a hernia will occur. There are problems with people handling potbellied pigs like farm pigs.
Castration is too traumatic for pet pigs.
Cryptorchidism - One or two testicles missing. This means the ring closed before the testicle had the chance to go outside. If a pig has one, it can breed, but cryptorchidism is a genetic situation. In the long run, there is proof that testicles that don't come out can turn into cancer. There are ethics involved.