rh negative blood type and pregnancy

i was wondering if anyone knows about or of any side effects from taking rh immune globulin. a doctor recently told me that since my blood is o negative there is a chance that my baby's blood could be treated as an invader (aka my body would build up antibodies against my own baby). the doctor has said that having a muscular injection of rh immune globulin (called WinRho) would prevent this yuckiness from occurring. ...while the thought of preventing the antibodies is super agreeable, i would like to know the pros and cons of this medical "cure" before i say yes to getting injected with the stuff. any info? Tweet