Erythroblastosis Fetalis: Mother vs. Baby

In Rubin’s Pathology: Clinicopathologic Foundations of Medicine, a textbook of massive proportions, a heading appears:

Erythroblastosis Fetalis is a Hemolytic Disease Caused by Mathernal Antibodies Against Fetal Erythrocytes

What does this mean? Well, in simpler terms courtesy of PubMed Health, erythroblastosis fetalis is a potentially life-threatening blood disorder in a fetus or newborn infant. There are two cases: ABO incompatibility, which is more common and varies in seriousness, and Rh incompatibility, which is less common. The incompatibility occurs between the blood of mother and baby while the babe is still in the womb.

I think many people are familiar with ABO blood types, in which a person may be A, B, AB, or O. But remember there can be a + or – after the ABO designation? That’s the Rh antigen typing. A little trivia:

The distribution of Rh antigens among ethnic groups varies. In American whites, 15% are Rh-negative (Rh D-), whereas only 8% of blacks are Rh D-. Japaneses, Chinese, and Native American Indian populations contain essentially no Rh D- persons. By contrast, in the Basque population, among whom the mutation that causes the Rh D- phenotype may have arisen, the prevalence of Rh D- persons is 35%. —– Rubin’s Pathology

For Rh incompatibile erythroblastosis fetalis, an Rh-negative mother may carry the first Rh-positive child without incident. However, during this pregnancy, the mother develops antibodies that are sensitive to, and would attack, Rh-positive red blood cells (RBCs) if she has a second Rh-positive child. A graphic depiction would be:

Thankfully, with RhoGAM®, administered within 72 hours of delivery, the incidents of Rh incompatible erythroblastosis fetalis have fallen.

As for ABO incompatible erythroblastosis fetalis, although it’s now more common than Rh incompatible erythroblastosis fetalis, rest assured, for prevention is possible with exchange transfusions and phototherapy.

So, ladies, talk to your doctor about the possibilities of this not-so-complicated-anymore-complication if you are planning on having a baby. Remember: you can always dump the blame on your husband 😉 because we all know it’s always the guy’s fault :-D.