Why Do Premature Babies Need Blood? Reasons You Have To Understand

I have handed over too many newborns to notice how they take their parents’ breath away every time. We have often witnessed mothers crying as their little one gets the first vaccine shot and newborn screening test. It goes without saying that babies in the NICU (neonatal intensive care unit), with all those tubes and needles, also break our hearts like a parent every time. Blood transfusion is one medical intervention that keeps us uneasy, especially when dealing with premature babies. But why do premature babies need blood in the first place?

There are several reasons why a newborn may need an immediate blood transfusion. It is common in preterm babies for treating anemia (anemia of prematurity) and babies with very low birth weight. Neonatal anemia happens when the baby does not produce enough red blood cells than what his body uses. In this case, he may need several transfusions right in the first few weeks of his life. Babies who have the risk of concurrent blood loss due to surgery and severe heart or lung disease also need a blood transfusion.

Why Would Babies Need Blood Transfusions?

When I first held Elijah, he was no bigger than a beer bottle, less than a kilogram in weight. His skin was bordering on a yellow to a pale color. He was struggling to breathe, that it’s distressing to feel his pulsating and delicate little body in my hands. It was my very first encounter with a struggling preemie.

He was born some six weeks shy of his expected arrival. What’s worse was that his mom, who had preeclampsia, needed some time in the ICU as well. So I said a little prayer for both mom and son.

I bothered to check on him while he was on the tubes. He was reunited with his mom and was doing amazing. After almost three months of hospital stay, he was unhooked and ready to go home with his hopeful parents. That was just the first, but never the last experience, that I have had with a premature baby. And I can at least say: all babies are born fighters.

Here are a few reasons why some babies may need blood transfusions:

Anemia of Prematurity

Preemies go through so many health conditions a couple of weeks after their births. For once, they are born with naturally low red blood cell counts (RBC) than full-term babies. Sometimes, this drop in the RBC can last longer and become lower that results in anemia. Anemia is common even to full-term babies and may get worse in premature infants.

A baby with anemia will have difficulty feeding as he tends to tire out easily. He may also develop pale skin, fast heart rate, and rapid breathing. Preemies are also prone to developing apnea, which is characterized by a sudden halt in breathing.

Blood transfusion is essential to babies with anemia. It will not only replace and supplement his RBC, but will also improve his feeding eventually. It may also improve apnea and help lessen his respiratory distress.

Baby Losses Too Much Blood

Frequent blood test samples extracted from preterm and sick babies also contribute to anemia. But these tests are necessary for managing your preemie’s condition and therefore unavoidable. 

The medical team will use blood to either diagnose his condition or see if he is reacting to medications.

Sadly, when these small blood samples add up, it will count as much loss for your baby. He will more likely end up needing additional blood to supplement his needs. How much blood he will need may depend on how sick or how small your baby is.

Baby has a Different Blood Group from His Mom

Babies naturally have a shorter red blood cell life span than adults. If he has a different blood group than that of his mum, his RBC will have an even shorter one. Inside his mommy’s tummy, her antibodies may start to wreak havoc on him.

I have a friend from back then who was struggling with her pregnancy. She has a couple of miscarriages, and the doctors ruled out that her antibodies were the culprit in attacking her embryos. 

Blood compatibility is a thing between couples. It may not affect your predisposition in marriage, but it may with your future biological children. Such is the baby’s inability to replace RBC quickly, which results in his need for blood transfusion.

The Baby Needs a Surgery

According to the Children’s Hospital of Orange County (CHOC), preterm babies are at high risk for health problems and surgeries. It can include severe lung and gastrointestinal disorders or heart defects. However, this is not only limited to preemies. Full-term babies may also undergo neonatal surgery to correct and treat certain conditions. Some procedures are even performed immediately after the baby is born. 

As far as surgery is concerned, bleeding is the most common complication. So it is understandable that your little one will need some blood transfusions during the surgery.

Low Platelet Count

Your baby may not always need the whole blood pack transfusion. A disease called thrombocytopenia may also happen in newborns. It is a condition where the baby does not make enough platelet. It can be a genetic condition or a result of bone marrow infection. If the mom has preeclampsia, it also limits the blood flow to the baby, resulting in a really low blood count.

When this happens, the baby will need a platelet transfusion instead of the whole blood components. It is to improve blood clotting and prevent him from bleeding.

Is Blood Transfusion Safe for Babies?

Is Blood Transfusion Safe for Babies?

We are always worrying about blood contamination in adults, so it is natural to question its safety in infants. But blood donors undergo rigorous screening, and their blood is thoroughly tested before the transfer. There will be physical examinations and perusing their medical history. Hence, the risk of the baby contracting an infection is very low.

Some parents may think that they can directly donate to their child if their blood type matches their baby’s. While this is possible, this is not often carried out. Parents will still undergo the same screening as volunteer donors to become eligible. Processing the blood donation may take a week or two to be safely available, so the baby cannot use it immediately.

Will There Be Risks and Side Effects in Transfusion?

Aside from donor testing, the blood will also be cross-matched to ensure that it is compatible with the baby. Your healthcare provider follows strict guidelines such as carefully double-checking the baby’s identity to prevent mismatching.

Babies will not likely feel any difference during a blood transfusion. But these risks and side effects may still happen:

  • Fever
  • Allergic reactions (rashes, itching, or hives)
  • Shortness of breath
  • Low-oxygen level
  • Mismatch blood (rare)

These side effects do not always happen. If it does happen, your doctor may recommend medications. The most prevalent problem that I have encountered while training happened with the IV lines. It may cause swelling or bruising of his skin around the area temporarily.

Blood mismatching is very rare in children and happens only in isolated cases. So don’t get annoyed about nurses asking repetitive questions for confirmation.

How to Take Care of a Preemie

How to Take Care of a Preemie

Even full-term babies are very delicate and anxiety-inducing to care for. With preemies, parents may undergo heightened stress. All those intravenous tubes mark the normal days of premature babies’ lives. He will have special needs that only the NICU can provide. It may look mostly distressing to parents, but always remember that those are vital to give them a better chance at survival.

On his first day, he will be given all the necessary fluids that he needs. As his condition stabilizes, he can start feeding through a tube. You can now feed him pumped milk or formula if it seems that he cannot tolerate your breast milk. Aside from feeding, here is how you can help your preemie.

  • Breastfeed if you can, it will reduce his risks of infections and SIDS risks
  • Interact with your baby during his feeding schedule (sing a song, talk to him, etc.)
  • Let your baby sleep and rest as he likes
  • Have skin-to-skin contact if his health allows
  • If the doctor does not allow holding the baby yet, you can still hold and caress his hands


Having a preemie may be a tough ride for you and the whole family. But don’t stress yourself out too much. The NICU is there to help your little one with his battle. Plus, you need to keep your fight strong by keeping yourself together.

Pay attention to your own and your other family members’ needs as well. You can also turn to other preemie parents in the NICU for support. The experience will not last long and your preemie will grow up as fine as other babies. Watching your baby grow stronger every day, one tube off after the other, is a great reward every parent can ever ask for.

Do you have a similar story with your preterm baby? How long was the NICU stay, and what helped you cope up? Other preemie parents would sure love to hear your preemie’s awesome journey.

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Ann Marie is a licensed nurse in the Philippines. She experienced handling and assisting deliveries of newborns into the world. She also trained in labor rooms and pediatric wards while in nursing school - helping soon-to-be mothers and little kids in the process. Though not a mother by nature but a mother by heart, Ann Marie loves to take care of her younger cousins as well as nephews and nieces during her free time.

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