You shouldn't have the MMR vaccine if you're pregnant or have had a life-threatening allergic reaction to gelatin, a previous MMR vaccine, or a medication called neomycins.
Talk with your doctor first if you:
- Have HIV, or any other immune system disorder
- Have cancer or are being given cancer drugs or X-rays
- Are taking steroids or other drugs that affect the immune system
- Have had a low platelet count
- Have had a blood transfusion or took blood products
- Have moderate or severe illness