The MMR vaccine usually requires 2 doses, or 3 doses in some areas. The MMR vaccine is used to prevent measles, mumps, and rubella. Due to the different CDCs in each region, the number of shots and vaccination schedule may vary. It is common for children to receive the first dose in August, the second dose at 18~24 months of age, and the third dose at 6 weeks of age may be recommended in some regions. It is important to note that when receiving the MMR vaccine, caution should be exercised if there is a family and personal history of convulsions, patients with chronic illnesses, a history of epilepsy, or allergies. MMR vaccine is one of the vaccines required by the state for children, so parents should take their children for this vaccine on time and regularly, and the family can consult with the local CDC for the specific number of vaccination shots.