Hemolytic disease of the newborn

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I asked my professor if a Rh- sensitized woman would pass her anti-Rh antibodies to an Rh- fetus, therefore being born sensitized. My prof said no. This confuses me because anti-Rh antibodies obviously pass through the placenta, otherwise hemolytic disease of the newborn would only begin at birth. Is my prof wrong?

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I don't believe the Rhogam injection given to the mother would be enough to allow the fetus to mount its own immune response. If that were the case, we wouldn't have to give children their own vaccines, we'd just give them to the mother during pregnancy.

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I asked my professor if a Rh- sensitized woman would pass her anti-Rh antibodies to an Rh- fetus therefore being born sensitized. My prof said no. This confuses me because anti-Rh antibodies obviously pass through the placenta, otherwise hemolytic disease of the newborn would only begin at birth. Is my prof wrong?[/quote']

If I'm understanding your question. Your prof. is correct. My rationale is because the mother is Rh+ and the fetus she is carrying is also....the mother's immune response does not look at the fetus blood type as foreign thus will not produce antibodies against this fetus. But if the mother is Rh positive and she is carrying a Rh- fetus than the mother's immune system would launch a antibody response to lysed that Rh- blood type of the fetus which does pass through the placenta. And in this situation yes the fetus would either die or be born with a hemolytic disease. That's y they always give the Rh factor to a Rh positive mother after giving birth the first time. Because of the likelihood of giving birth the nxt time to a Rh- baby. In addition this problem does not affect the first born only those born after the first child if it is Rh-. So the factor is basically giving prophylactically. Hope I didn't complicate things for u and this helped.

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If I'm understanding your question. Your prof. is correct. My rationale is because the mother is Rh+ and the fetus she is carrying is also....the mother's immune response does not look at the fetus blood type as foreign thus will not produce antibodies against this fetus. But if the mother is Rh positive and she is carrying a Rh- fetus than the mother's immune system would launch a antibody response to lysed that Rh- blood type of the fetus which does pass through the placenta. And in this situation yes the fetus would either die or be born with a hemolytic disease. That's y they always give the Rh factor to a Rh positive mother after giving birth the first time. Because of the likelihood of giving birth the nxt time to a Rh- baby. In addition this problem does not affect the first born only those born after the first child if it is Rh-. So the factor is basically giving prophylactically. Hope I didn't complicate things for u and this helped.

Sorry just retread your post again. Think I'm responded in correctly. Haha. Are u asking if both the mother and fetus is Rh- would the mother launch an antibody attack against the fetus? If so the principal is still the same. She wouldn't because the Rh is the same as her. It only becomes a problem when the mother is Rh+ and the fetus is Rh-. It is not even a problem ( from my understanding) if the mother is Rh- and the fetus is Rh+. And again this situation becomes a problem when she conceives for the second time , it does not affect the first born. So Rhogam is always given to a Rh+ mother during her pregnancy and again after the delivery. Hope this helps.?

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Specializes in Pedi.
Sorry just retread your post again. Think I'm responded in correctly. Haha. Are u asking if both the mother and fetus is Rh- would the mother launch an antibody attack against the fetus? If so the principal is still the same. She wouldn't because the Rh is the same as her. It only becomes a problem when the mother is Rh+ and the fetus is Rh-. It is not even a problem ( from my understanding) if the mother is Rh- and the fetus is Rh+. And again this situation becomes a problem when she conceives for the second time , it does not affect the first born. So Rhogam is always given to a Rh+ mother during her pregnancy and again after the delivery. Hope this helps.

The problem occurs in an Rh NEGATIVE mother pregnant with an Rh positive fetus. Why would an Rh positive mother have an issue with an Rh negative fetus? The mother has the Rh factor and the fetus does not... so there's nothing for the mother's body to recognize as foreign.

Rh incompatibility becomes an issue when fetal and maternal blood are mixed. The mother's Rh negative immune system recognizes the Rh factor as foreign and makes anti-Rh antibodies. Then the next time fetal and maternal blood come into contact, the mother's anti-Rh antibodies attack the fetus's Rh positive blood. It's not true that it's "only" an issue in subsequent pregnancies... in most cases, Rh incompatibility does not affect the first born because fetal and maternal blood usually do not mix during pregnancy but there are certain situations in which they can. If a woman gets into a car accident or something which causes mixing of the blood, she then will make antibodies during pregnancy and the fetus could be at risk.

Rhogam is not given to Rh+ women. Rh + women do not form antibodies against the Rh factor because they have it and their body does not recognize it as a foreign antigen that needs to be attacked.

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Specializes in Pedi.

Now, I believe that the OP's question (correct me if I'm wrong, OP) is this: An Rh negative mother who has previously been exposed to the Rh factor and now has natural antibodies against it is carrying an Rh negative fetus. Will the antibodies cross the placenta and get into fetal circulation? I'd side with your professor on this... Anti-RH antibodies CAN cross the placenta but they do so when the mother is carrying an Rh positive fetus because the body recognizes the Rh factor as foreign and tries to attack it. With an Rh negative fetus, these anti-Rh antibodies have no Rh factor in the fetus to go looking for.

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If I'm understanding your question. Your prof. is correct. My rationale is because the mother is Rh+ and the fetus she is carrying is also....the mother's immune response does not look at the fetus blood type as foreign thus will not produce antibodies against this fetus. But if the mother is Rh positive and she is carrying a Rh- fetus than the mother's immune system would launch a antibody response to lysed that Rh- blood type of the fetus which does pass through the placenta. And in this situation yes the fetus would either die or be born with a hemolytic disease. That's y they always give the Rh factor to a Rh positive mother after giving birth the first time. Because of the likelihood of giving birth the nxt time to a Rh- baby. In addition this problem does not affect the first born only those born after the first child if it is Rh-. So the factor is basically giving prophylactically. Hope I didn't complicate things for u and this helped.

Thank you for your corrections!!! As I have read up I did confuse the Rh+ and Rh- mother. It would be an Rh- mother who is carrying a Rh+ fetus that would have problems. AGAIN it does not become an issue with the first born but rather those who come after the firstborn. And Rhogam is given to the Rh- mother as you stated not the Rh positive mother. Apologize for any confusion to the OP. and to the one who posted after me...I don't need to be hostile in your corrections. As no one knows everything!!!! I am grateful that u corrected the post. But take a chill pill all the TUDE and know it all attitude is NOT NECESSARY!!!! I'm believe we all are here to learn from one another. To the OP again apologize for the mixup with the Rh- mother. But the other info still remains the same. Thank you. I'm a lover not a fighter!!! Haha

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Specializes in Pedi.
Thank you for your corrections!!! As I have read up I did confuse the Rh+ and Rh- mother. It would be an Rh- mother who is carrying a Rh+ fetus that would have problems. AGAIN it does not become an issue with the first born but rather those who come after the firstborn. And Rhogam is given to the Rh- mother as you stated not the Rh positive mother. Apologize for any confusion to the OP. and to the one who posted after me...I don't need to be hostile in your corrections. As no one knows everything!!!! I am grateful that u corrected the post. But take a chill pill all the TUDE and know it all attitude is NOT NECESSARY!!!! I'm believe we all are here to learn from one another. To the OP again apologize for the mixup with the Rh- mother. But the other info still remains the same. Thank you. I'm a lover not a fighter!!! Haha

It usually is not an issue with the firstborn, but as I explained in my previous post, it can be. The reason why it is usually not an issue in the firstborn is because fetal and maternal blood usually do not mix during pregnancy. The Rh negative mother's body first needs exposure to the Rh factor to begin producing antibodies. In most cases, delivery is the first exposure which is why the first born is usually unaffected. However, to say as a blanket statement "it does not become an issue with the firstborn" is false. The first born could very easily not be the result of a first pregnancy- if the mother had a previous abortion, miscarriage, ectopic pregnancy, she could already have anti-Rh antibodies. (In your OB clinical, do you recall them describing women as "G3, P0-1"? So this woman was pregnant twice before delivering her first born, the first born could very easily be at risk.) If the mother gets into a car accident or experiences some sort of abdominal trauma while pregnant (even with her first pregnancy), fetal blood can enter maternal circulation, which would expose the mother to the Rh factor and her body would begin producing anti-Rh antibodies which could very well affect the fetus she is currently pregnant with... even if it is the first pregnancy. I once had a patient who had MANY issues because his mother was kicked in the belly by a horse while pregnant.

I don't know what attitude you're talking about... the OP asked a question, incorrect information was posted and I clarified it.

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It usually is not an issue with the firstborn, but as I explained in my previous post, it can be. The reason why it is usually not an issue in the firstborn is because fetal and maternal blood usually do not mix during pregnancy. The Rh negative mother's body first needs exposure to the Rh factor to begin producing antibodies. In most cases, delivery is the first exposure which is why the first born is usually unaffected. However, to say as a blanket statement "it does not become an issue with the firstborn" is false. The first born could very easily not be the result of a first pregnancy- if the mother had a previous abortion, miscarriage, ectopic pregnancy, she could already have anti-Rh antibodies. (In your OB clinical, do you recall them describing women as "G3, P0-1"? So this woman was pregnant twice before delivering her first born, the first born could very easily be at risk.) If the mother gets into a car accident or experiences some sort of abdominal trauma while pregnant (even with her first pregnancy), fetal blood can enter maternal circulation, which would expose the mother to the Rh factor and her body would begin producing anti-Rh antibodies which could very well affect the fetus she is currently pregnant with... even if it is the first pregnancy. I once had a patient who had MANY issues because his mother was kicked in the belly by a horse while pregnant.

I don't know what attitude you're talking about... the OP asked a question, incorrect information was posted and I clarified it.

Your so right. Thanx for the clear up. Have a good life.

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It usually is not an issue with the firstborn, but as I explained in my previous post, it can be. The reason why it is usually not an issue in the firstborn is because fetal and maternal blood usually do not mix during pregnancy. The Rh negative mother's body first needs exposure to the Rh factor to begin producing antibodies. In most cases, delivery is the first exposure which is why the first born is usually unaffected. However, to say as a blanket statement "it does not become an issue with the firstborn" is false. The first born could very easily not be the result of a first pregnancy- if the mother had a previous abortion, miscarriage, ectopic pregnancy, she could already have anti-Rh antibodies. (In your OB clinical, do you recall them describing women as "G3, P0-1"? So this woman was pregnant twice before delivering her first born, the first born could very easily be at risk.) If the mother gets into a car accident or experiences some sort of abdominal trauma while pregnant (even with her first pregnancy), fetal blood can enter maternal circulation, which would expose the mother to the Rh factor and her body would begin producing anti-Rh antibodies which could very well affect the fetus she is currently pregnant with... even if it is the first pregnancy. I once had a patient who had MANY issues because his mother was kicked in the belly by a horse while pregnant.

I don't know what attitude you're talking about... the OP asked a question, incorrect information was posted and I clarified it.

Btw I humbly accept the clarifications.?

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Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.

I don't think KelRN had an attitude at all I found her post 100% accurate and informative and answered the OP's question.....she is also 100% correct.

As an Rh- mother is is not with the first pregnancies that cause this issue it is after the Mother has has subsequent pregnancies that the mother has built up anti-bodies from the Rh+ fetus that will then affect the next pregnancy. This used to also be called having a "blue baby"

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