No, but you are likely to gain weight.
My sister did! The shot is not 100% effective---just the same as any other form of birth control.
Yeah, that's scary that some people think that there is birth control that is 100% effective. THERE IS NO BIRTH CONTROL THAT IS 100% EFFECTIVE EXCEPT ABSTINENCE. I can't believe that you have never heard that.
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I've been pregnant on it before (i miscarried because of the depo) and i think i may be pregnant again.