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What is fetal blood transfusion?

A fetal blood transfusion is a procedure used to treat anemia in the fetus. Fetal anemia occurs when the baby’s blood count is too low. The condition can be life threatening, which is why fetal blood transfusions need to be conducted shortly after discovering fetal anemia.

A fetal blood transfusion replaces the red blood cells that may have been destroyed by an infection or Rh incompatibility. Rh incompatibility occurs when the mother and her developing baby have different blood types, causing antibodies in the mother’s blood to destroy red blood cells in the baby’s blood.

Fetal blood transfusions are the most successful approach for transfusing blood directly into the baby and often lead to rapid improvement in the baby’s health. In most cases, these transfusions occur between 19 and 35 weeks of completed pregnancy.

Guided by an ultrasound, they are administered through a needle in the maternal abdomen, which is then inserted into the umbilical cord or fetal abdomen in rare cases. Additional transfusions may be needed to keep the baby healthy until he or she is ready for delivery.

Our approach

For a fetal blood transfusion, you will have access to cutting-edge technology and some of the best diagnostic equipment in the region. A team of highly trained physicians, sonographers and nurses will study your medical history, conduct an in depth evaluation and order the proper tests to make an accurate diagnosis.

In most cases, our specialists can determine if a fetal blood transfusion is needed based off the findings of an ultrasound and blood tests.

If you need a fetal blood transfusion, we have the support services to completely handle your treatment, from the transfusion itself to early delivery in the event of an emergency. Our state-of-the-art technology, multidisciplinary specialists and collaborative approach allow us to offer excellent care every step of the way.

Why it's done

Fetal blood transfusions are needed when fetal anemia is discovered. If you have had previous pregnancies that required blood transfusions or your blood is found to be containing red blood cell antibodies, your baby may be closely monitored for fetal anemia.

If your baby is at risk of developing anemia, your physician will order a Doppler ultrasound to examine the fetal middle cerebral artery. Changes to blood flow in this artery suggests fetal anemia. In severe cases, swelling and fluid collection in the baby’s tissue and organs are discovered in the ultrasound. These are signs of heart failure and may require an emergency transfusion. Our specialists will conduct the transfusion as soon as the donated blood is ready, which typically takes up to 12 hours.


Because fetal blood transfusions are invasive procedures, there are a handful of risks associated with the treatment, including:

  • Infection to the mother, baby or both
  • Fetal bleeding
  • Blood clots that may cause the baby’s heart rate to drop
  • Emergency casarean section (C-section) in rare cases

How to prepare

Ahead of your fetal blood transfusion, you will be told not to eat or drink anything after midnight before your procedure. You will also receive steroid injections as a precaution. These injections help develop your baby’s lungs in case he or she needs to be delivered through an emergency C-section. You will also be given antibiotics to reduce the risk of infection.

On the day of the procedure, you will be offered optional local anesthesia. Your baby may also be given medicine to temporarily stop fetal movement during the procedure.

A fetal blood transfusion typically lasts anywhere from 15 to 30 minutes. During this time, your physician takes a blood sample from the baby to analyze the blood count and confirm fetal anemia. If fetal anemia is confirmed, your physician will begin the transfusion. The amount of blood transfused is based on the blood count and size of the fetus. Another sample will be taken after the transfusion is completed to confirm the baby’s blood count is healthy.

What to expect after treatment

After the transfusion is finished, the needle is removed and your baby’s health is confirmed, you will be transferred to labor and delivery for several hours of monitoring.

It may take a few hours until you can feel your baby move again, as the medicine gradually wears off. Once the medication has worn off both you and your baby, you can be discharged the same day. You may feel cramping and soreness after the procedure.

A follow-up appointment is needed within the next few days. Additional transfusions may be needed depending on how far you are in your pregnancy and your baby’s condition. Your physician will be able to answer any questions you have and explain why you do or do not need additional transfusions.

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