The MMR vaccine protects against the measles, mumps and rubella.
Most side effects are mild, manageable and do not last long. The most common mild side-effects are local (sore and red area), feeling unwell, crying (babies) and fever.
There can be very rare side effects, like allergic reactions or encephalitis.
However, the risks for not having the vaccination outweigh the risks of having the vaccination, due to the risks of severe complications from measles if you’re not vaccinated. (1)