Rabbits reach sexual maturity between 3-8 months old. If you don't spay/neuter your rabbit there are personality changes that can take place. Your rabbit may spray you, be very clingy, show territorial aggression, chew and dig destructively and more annoying behaviors. Female bunnies have a higher risk of uterine cancer if not spayed. Neutering is not an unnecessary surgery and is definitely recommended, particularly if you have both male and female bunnies.