Rh-negative blood, specifically when the fetus is Rh-positive, can cause complications during pregnancy if not properly managed.
Here's a breakdown:
The issue revolves around Rh factor, a protein found on the surface of red blood cells. You are either Rh-positive (you have the protein) or Rh-negative (you don't). Problems arise when an Rh-negative mother carries an Rh-positive fetus.
Why is Rh Incompatibility a Problem?
During pregnancy, especially during delivery, some of the baby's blood can enter the mother's circulation. If the mother is Rh-negative and the baby is Rh-positive, the mother's immune system recognizes the Rh protein as foreign and starts producing antibodies against it. This is called Rh sensitization.
Consequences of Rh Sensitization:
-
First Pregnancy: Usually, the first pregnancy isn't significantly affected because the mother hasn't produced enough antibodies to cause problems.
-
Subsequent Pregnancies: In subsequent pregnancies with Rh-positive babies, these antibodies can cross the placenta and attack the baby's red blood cells, leading to hemolytic disease of the fetus and newborn (HDFN). HDFN can cause anemia, jaundice, brain damage, and even death in the fetus or newborn.
Prevention and Treatment
Fortunately, Rh incompatibility is easily preventable. Rh-negative mothers receive an injection of Rh immunoglobulin (RhIg or RhoGAM). RhIg prevents the mother's immune system from recognizing the Rh-positive blood cells and forming antibodies.
When is RhIg Administered?
- Around 28 weeks of pregnancy
- Within 72 hours after delivery if the baby is Rh-positive
- After any event that could cause mixing of fetal and maternal blood (e.g., miscarriage, abortion, ectopic pregnancy, amniocentesis, or abdominal trauma).
With proper management, Rh incompatibility is rarely a serious problem today.
