Texas Fetal Center
Fetal anemia is an inadequate number or quality of red blood cells in the fetal circulatory system. Red blood cells carry oxygen to the cells and organs within the body. Anemia can lead to many complications in the fetus. As with many fetal conditions, anemia can range from mild to severe. If the anemia is severe, the fetal heart tries to overcome the inadequate number or quality of red blood cells by pumping harder. This can result in fetal heart failure (hydrops).
The most common reason for fetal anemia occurs when the baby has a specific difference in blood antigens or proteins from the mother. This is referred to as alloimmunization. This happens when the baby inherits certain blood antigens from the father that the mother does not have. The mother's system can create antibodies that attack the fetal cells. This leads to the destruction of the fetal red blood cells and, eventually, to fetal anemia.
Another cause of anemia can be one of several maternal infections, such as Parvovirus, a common childhood illness. There are blood tests that can be done to confirm a recent or past infection with this virus.
Fetal anemia can also be the result of blood loss from the fetal circulation. There are other more rare conditions that can cause anemia as well. These include structural fetal abnormalities or masses such as a sacrococcygeal teratoma.
Fetal anemia may be diagnosed in several ways:
Fetal anemia is monitored and treated prenatally by several methods. Your care plan might include frequent monitoring to measure the blood flow in the MCA. If the anemia is moderate to severe, a fetal blood sampling and transfusion may be necessary. Under ultrasound visualization, compatible red blood cells are transfused through the umbilical vein. This procedure is very similar to the procedure performed to obtain a sample of fetal blood. It is a longer procedure and is performed in a hospital setting. In some cases the mother may need to stay overnight. Both mother and fetus are monitored during and after the procedure until fetal and maternal well being are established. This procedure may need to be repeated every 1- 4 weeks depending on the fetal condition.
Newborns generally do well after birth. Newborn jaundice may occur and can be severe. Jaundice occurs when the newborn's bilirubin level is too high. Bilirubin is a substance that is found in red blood cells. Jaundice is monitored by lab tests. Mild cases of jaundice may only require careful monitoring of the newborn. If the newborn's bilirubin is too high, the neonatologist or pediatrician may need to treat the baby to bring down the bilirubin level. If this situation develops, your doctors will discuss potential treatments. The baby can still be breast fed and spend time with the parents. The mother will need to be evaluated in future pregnancies for possible fetal anemia.
Contact the Texas Fetal Center to make an appointment with a high-risk pregnancy doctor.
Note: This information regarding your condition is meant to be a helpful, informative introduction. Because every newborn is different, this may not be applicable to all cases, especially if there are additional defects. Your team of experts at the Center will provide you with information specific to your pregnancy.