Rh factor is a protein found on the surface of red blood cells. If your blood has the protein, you’re Rh positive. If your blood lacks the protein, you’re Rh negative. Understanding your Rh factor is crucial, especially during pregnancy, as it can significantly impact both the mother’s and baby’s health.
Understanding Rh Factor: Positive vs. Negative
About 85% of people are Rh positive, meaning they have the Rh factor protein on their red blood cells. The remaining 15% are Rh negative, lacking this protein. This distinction, seemingly minor, can have major implications when it comes to blood transfusions and pregnancy.
Rh Factor and Pregnancy: Potential Complications
Rh incompatibility arises when an Rh-negative mother carries an Rh-positive fetus. This can occur if the father is Rh positive. While the mother’s and baby’s blood don’t typically mix during pregnancy, small amounts of the baby’s blood can enter the mother’s bloodstream during delivery or certain prenatal procedures like amniocentesis or chorionic villus sampling (CVS).
If an Rh-negative mother is exposed to Rh-positive blood, her immune system recognizes the Rh factor as foreign and produces antibodies against it. This process, called sensitization, usually doesn’t affect the first pregnancy. However, in subsequent pregnancies with an Rh-positive fetus, these antibodies can cross the placenta and attack the baby’s red blood cells. This condition, known as Rh disease or hemolytic disease of the newborn (HDN), can lead to severe complications for the baby, including anemia, jaundice, and even death.
Preventing Rh Disease: Rh Immunoglobulin (RhoGAM)
Fortunately, Rh disease is preventable. Rh-negative mothers who are pregnant or have recently given birth to an Rh-positive baby can receive an injection of Rh immunoglobulin (RhoGAM). This medication prevents the mother’s immune system from producing antibodies against the Rh factor.
RhoGAM is typically administered around the 28th week of pregnancy and again within 72 hours after delivery. It’s also recommended after any potential exposure to fetal blood, such as miscarriage, ectopic pregnancy, or abdominal trauma.
Rh Factor and Blood Transfusions
Rh factor is also critical in blood transfusions. An Rh-negative person can only receive Rh-negative blood. Receiving Rh-positive blood can trigger a potentially life-threatening immune response, where the body attacks the transfused blood cells.
Conclusion: The Importance of Knowing Your Rh Factor
Knowing your Rh factor is vital for your health and, if you’re a woman, for the health of your future children. It allows healthcare providers to take necessary precautions, such as administering RhoGAM, to prevent potential complications arising from Rh incompatibility. If you’re unsure of your Rh factor, a simple blood test can provide the answer. Talk to your doctor to learn more.
