Resource
Common Terms During an Alloimmunized Pregnancy
Pregnancy Guidelines
Share
Navigating a pregnancy complicated by maternal alloimmunization can feel overwhelming, especially when healthcare providers use unfamiliar medical terminology.
Understanding Alloimmunization and HDFN: A Comprehensive Glossary
This comprehensive glossary is designed to help expectant parents and families understand the key terms, tests, and treatments associated with alloimmunization and Hemolytic Disease of the Fetus and Newborn (HDFN).
From initial antibody screening to specialized monitoring techniques like Middle Cerebral Artery Doppler scans, this resource breaks down complex medical concepts into clear, accessible explanations. Whether you’re trying to understand what a critical titer means, learning about potential treatments like intrauterine transfusions, or simply wanting to better comprehend your care team’s discussions, this glossary serves as your reference guide throughout your pregnancy journey.
When your immune system forms antibodies against your baby’s red blood cells due to antigen mismatch. This can lead to HDFN.
A test where a small amount of amniotic fluid is removed to check if the baby has the antigen.
This is rarely needed today but still used in some cases.
A protein made by your immune system. In maternal alloimmunization, these antibodies target your baby’s red blood cells.
A test that checks for the presence of red blood cell antibodies in the mother’s blood.
A marker on red blood cells. If your baby inherits an antigen you don’t have, your body may see
it as foreign and create antibodies against it.
A yellow substance released when red blood cells break down; high levels cause jaundice.
A blood test done on the mother that looks for the baby’s DNA to determine if the baby has the
antigen.
A liver issue that can cause jaundice to last longer, sometimes seen in babies with HDFN.
A procedure to sample or transfuse blood from the baby’s umbilical cord.
The titer level at which doctors begin special monitoring. This varies by antibody type (often
1:16 for anti-D, for example).
A test on the baby’s blood to check for antibody-coated red cells, indicating HDFN.
Medications that help stimulate red blood cell production in babies.
A treatment where most or all of baby’s blood is replaced to remove antibodies and excess bilirubin. Used in severe post-birth cases.
A measure of stored iron. Babies with HDFN may have high levels and do not usually need iron
supplements.
When the baby doesn’t have enough red blood cells to carry oxygen, often due to antibody destruction.
Non-stress tests to check the baby’s heart rate and movements.
A condition where antibodies break down a baby’s red blood cells, leading to anemia and other
complications before or after birth.
The percentage of red blood cells in blood. Used to monitor anemia.
A medical specialty focused on blood disorders. Babies with HDFN are often followed by a
pediatric hematologist.
A severe complication where fluid builds up in the baby’s body due to anemia and causes heart
failure.
Another name for the antibody screen.
A procedure where blood is given directly to the baby before birth to treat anemia. Done by specialists if the baby becomes severely anemic.
A treatment sometimes used to slow antibody activity or delay the need for an exchange transfusion after birth.
Anemia that appears weeks after birth due to delayed bone marrow recovery.
A high-risk pregnancy specialist, often called a perinatologist.
An ultrasound that measures blood flow in the baby’s brain to detect anemia.
A blood test to see if the baby’s father carries the antigen that the mother has antibodies against. If he doesn’t, the baby isn’t at risk.
A treatment using special lights after birth to reduce high bilirubin levels (a result of red blood cell breakdown).
A test that shows if the baby’s body is making new red blood cells.
Given before early delivery to help baby’s lungs mature for birth.
A blood test that shows how much antibody is in your system. Higher numbers can mean more risk, but titers aren’t always predictive in all cases.
A blood transfusion to treat anemia after birth.
Related Resources
View All
Pregnancy Guidelines
Finding the Right Path to Grow Your Family
Birth and Infant Follow-Up
HDFN Birth and Infancy Care Guide
Pregnancy Guidelines
Pregnancy Support for Maternal Alloimmunization
Pregnancy Guidelines