HDN happens most often when an Rh negative mother has a baby with an Rh positive father. If the baby's Rh factor is positive, like his or her father's, this can be an issue if the baby's red blood cells cross to the Rh negative mother.
This often happens at birth when the placenta breaks away. But it may also happen any time the mother’s and baby's blood cells mix. This can occur during a miscarriage or fall. It may also happen during a prenatal test. These can include amniocentesis or chorionic villus sampling. These tests use a needle to take a sample of tissue. They may cause bleeding.
The Rh negative mother’s immune system sees the baby's Rh positive red blood cells as foreign. Your immune system responds by making antibodies to fight and destroy these foreign cells. Your immune system stores these antibodies in case these foreign cells come back again. This can happen in a future pregnancy. You are now Rh sensitized.
Rh sensitization normally isn’t a problem with a first pregnancy. Most problems occur in future pregnancies with another Rh positive baby. During that pregnancy, the mother's antibodies cross the placenta to fight the Rh positive cells in the baby's body. As the antibodies destroy the cells, the baby gets sick. This is called erythroblastosis fetalis during pregnancy. Once the baby is born, it’s called HDN.
HDN is about 3 times more common in Caucasian babies than in African-American babies.
During pregnancy, you won't notice any symptoms. But your healthcare provider may see the following during a prenatal test:
After birth, symptoms in your baby may include:
The following tests are used to diagnose HDN after your baby is born:
During pregnancy, treatment for HDN may include the following.
A healthcare provider will check your baby’s blood flow with an ultrasound.
This test puts red blood cells into your baby's circulation. In this test, a needle is placed through your uterus. It goes into your baby’s abdominal cavity to a vein in the umbilical cord. Your baby may need sedative medicine to keep him or her from moving. You may need to have more than 1 transfusion.
If your baby gets certain complications, he or she may need to be born early. Your healthcare provider may induce labor may once your baby has mature lungs. This can keep HDN from getting worse.
After birth, treatment may include the following.
This may be done if your baby has severe anemia.
This may be done if your baby has low blood pressure.
In this test, your baby is put under a special light. This helps your baby get rid of extra bilirubin.
Your baby may need oxygen, a substance in the lungs that helps keep the tiny air sacs open (surfactant), or a mechanical breathing machine to breathe better.
This test removes your baby’s blood that has a high bilirubin level. It replaces it with fresh blood that has a normal bilirubin level. This raises your baby’s red blood cell count. It also lowers his or her bilirubin level. In this test, your baby will alternate giving and getting small amounts of blood. This will be done through a vein or artery. Your baby may need to have this procedure again if his or her bilirubin levels stay high.
IVIG is a solution made from blood plasma. It contains antibodies to help the baby's immune system. IVIG reduces your baby’s breakdown of red blood cells. It may also lower his or her bilirubin levels.
When your baby’s red blood cells break down, bilirubin is formed. It’s hard for babies to get rid of bilirubin. It can build up in their blood, tissues, and fluids. This is called hyperbilirubinemia. Bilirubin makes a baby’s skin, eyes, and other tissues to turn yellow. This is called jaundice.
When red blood cells breakdown, this makes your baby anemic. Anemia is dangerous. In anemia, your baby’s blood makes more red blood cells very quickly. This happens in the bone marrow, liver, and spleen. This causes these organs to get bigger. The new red blood cells are often immature and can’t do the work of mature red blood cells.
Complications of HDN can be mild or severe.
During pregnancy, your baby may have the following:
After birth, your baby may have the following:
If you’re Rh negative and have not been sensitized, you’ll get a medicine called Rh immunoglobulin (RhoGAM). This medicine can stop your antibodies from reacting to your baby’s Rh positive cells. Many women get RhoGAM around week 28 of pregnancy.
If your baby is Rh positive, you’ll get a second dose of medicine within 72 hours of giving birth. If your baby is Rh negative, you won’t need a second dose
Tips to help you get the most from a visit to your child’s healthcare provider: