I don't know a whole lot about this topic. However, I would urge you to look into the consequences of NOT getting RhoGAM. My sister has had over 10 first trimester miscarriages because her doctor forgot to give her the RhoGAM shot. She is now sensitized to the Rh+ blood of her unborn babies, and her immune system fights off the babies blood causing a hemolytic disease and eventually miscarriage. If you are Rh negative and have an Rh positive baby, if you do not get the shot and become pregnant again with an Rh positive baby, you run the risk of miscarriage anytime from conception to birth. Not saying I'm right or wrong...just talk to your doctor before just refusing the shot. It has caused a lot of sadness in my sisters life.