Is it true that it can be harmful unless you undergo an special injection?
  I have negative RH and somehow scared of what I heard about it....

  Yes. I was even told the scientific explanation of how it works. But as I am growing more and more suspecious of many kinds of 'science' and see more cases of healthy people living normal lives inspite of having "risk factors", I wanted to make sure that this one is not a lie.

You need a shot of Rhogam if the father does not share the same blood type.  I think they give it right before delivery, can't remember.  

The shot stops what was called "blue babies" and saves lives.  Otherwise the baby is being fought off as an antibody or something.

So it is not like risking a vaccine at all, this one is real.

Clare, if you had RH- blood, they would have told you.  It is very rare.

LOL, long Live the Queen!

Cant help but comment on this. Ok my Ex husband had type A+ and I have type B+. I am sure our 5 kids have a mix inbetween but they say as long as the + or - is not mixed together you dont have the RH factor problems. I am not sure about that and I am not an expert. On an interesting note,there is sufficiant evidence that the people who have + type blood were the ones who survived the dramatic plagues back in the old world. As a B+ blood type I am evidence of some of my successfully immuned grandparents as are all of us. The reason the Europeans were able to overtake the majority of the Americas is because of the small pox (and of course the very obvious reason of Our Lord and Lady). So Praise be to God for our immune systems and the technology to help those with Rh factor.

Clare, if you had RH- blood, they would have told you.  It is very rare.

So, I guess my husband's blood group would only matter if I were RH-.

Is it not a problem if the wife is + and the husband - though?

Obstetricians routinely give Rhogam at 28 weeks gestation and with 72 hours of giving birth.  Rhogam prevents your body from developing a sensitivity to your baby's RH+ blood type.  This sensitivity occurs when your RH- blood mixes with your  baby's RH+ blood.  Rhogam is given in early pregnancy after the first trimester in case of injury to the womb, breakdown of the placenta membrane, amniocentesis, and external version.  The baby's blood can mix during and after birth if the placenta detached early, the placenta was removed aggressively by cord traction or external manipulation of fundus, or the cord was clamped before it stopped pulsating causing blood to back up into the placenta.  If this does occur you have 72 hours to receive Rhogam before your body starts producing antibodies to fight off the offending red blood cells.  Rhogam is said to be about 93% effective, and 2% still develop a sensitivity .  If your body does develop these antibodies your future children would be at risk for  hemolytic disease, jaundice, brain damage, heart problems or fetal death.  Before Rhogam  it was said that between 12 and 16% of RH- mothers developed these antibodies.  In homebirth and midwifery case studies the instance of mother developing these antibodies was nearly zero.  
I personally had many Rhogam shots before I was an informed mother.  There has never been a study to determine if the shots become ineffective after receiving them routinely.  Rhogam contains 30 micrograms of thimerosal it is unknown what effect this has on a fetus.  On case study suggest there is higher rate of autism among RH- women who receive  Rhogam while pregnant.  I have been tested and shown no signs of sensitivity, I no longer receive Rhogam while pregnant, but I Will probably get it postpartum if my baby has Rh+ blood.  

Never takin' that again, then.

 :sad: