A Maltese puppy reaches its adult size when it is 10 to 12 months old. Maltese puppies reach their adolescence and become sexually active at six months of age, so experts recommended spaying or neutering them before then.
Full-grown Maltese dogs should weigh 4 to 6 pounds, with 7 pounds being the maximum healthy weight for the breed. They measure 8 to 10 inches in height. Experts advise owners not to take Maltese puppies younger than eight months for long walks, as their bones are not fully developed until this age. The average lifespan of a Maltese dog is 12 to 15 years.