Rh Factor & Pregnancy: Understanding RhoGAM and Miscarriage History

Question
I am 23 years old and I am pregnant with our first child.  The first day of my last period was Nov. 1st. I have had one miscarriage a little over a year ago.  I found out at the time that i am RH -  I got the Rogam shot and was only 4-6 weeks along.  My aunt is also RH - and insists that i need to get the shot ahead of time.  She said that she had one a head of time after 4 miscarriages.  Well now she is telling me that I need to go immediatly and get the shot now that i am pregnant or I am going to loose this one too.  She has everyone freaked out.  I called my Doctors office and talked to a nurse who has been with my Doctor for 17 years.  She said they have NEVER given teh shot before conception and only give it earlier then 28 weeks if there is bleeding or a chance of internal bleeding.  They said if i got the shot now it would not prevent me of having another miscarriage now.  My aunt does not believe them and is hounding me to see HER doctor.  Could you please give me some insite on this?  Any advice that i could show my aunt to make her leave me alone would be great.  Or is she right?

Thank you in advance,

Rachel B.

Answer
Your aunt is wrong and her doctor will confirm it. If you have Rh negative blood and your husband has Rh positive blood, you need to get a RhoGam shot at 28 weeks gestation and again within 72 hours after the baby is born, so that you do not become sensitized (so that your body will not build up antibodies to Rh factor). After any miscarriage, we also give a shot of RhoGam for the same reason. RhoGam injections do not prevent miscarriages. They do prevent the sensitization that can occur if you produce antibodies to the Rh factor. If you develop antibodies, these antibodies can cross the placenta and cause "erythroblastosis faetalis" or "blue baby syndrome" which can cause the death of your baby. They do not cause miscarriage. RhoGam is NOT given at the beginning of pregnancy or ahead of the time it is needed. It is ONLY given at 28 weeks and at delivery (and if you have miscarried or had a D&C for a miscarriage. If you have any further questions, do not hesitate to call on me. Good Luck with your pregnancy.