Alpha thalassemia is an inherited blood disorder. This means it is passed down through the parent’s genes. It causes anemia in affected children. Anemia is a low red blood cell or low hemoglobin level. Hemoglobin is the part of red blood cells. It carries oxygen to organs, tissues, and cells. Alpha thalassemia affects the production of hemoglobin.  

There are different types of thalassemia. The severity of anemia depends on the type the child has.


Alpha thalassemia is caused by defects in the genes that control hemoglobin production. There are 3 types:

  • Alpha thalassemia major (also called Hb Bart syndrome). This is a very serious form that develops before birth. It causes hydrops fetalis. This is a condition in which the body has too much fluid among other serious problems. Most affected babies are stillborn. Or they die soon after birth. The mother can also have serious, life-threatening complications.
  • Hemoglobin H disease (HbH disease). Hemoglobin H disease causes anemia that ranges from mild to severe. The symptoms most often start in childhood. Affected people are at increased risk for having a child with alpha thalassemia major.
  • Alpha thalassemia carrier. There are 2 types of carriers.
    • A carrier can have the trait. This means he or she has mild symptoms but can pass the gene on to children. 
    • A carrier may be silent. This means he or she doesn’t have symptoms, but can still pass the gene onto children.

Risk Factors

Alpha thalassemia is passed from parents to children. They way it is inherited varies and is complex. If both parents have the gene defect, each of their children has a risk of having alpha thalassemia major. They are also at risk for having hemoglobin H disease, and of being a carrier.

The gene defect that causes alpha thalassemia is more common in people from these areas:

  • Mediterranean countries
  • North Africa
  • Middle East
  • India
  • Central Asia


Symptoms of alpha thalassemia are from anemia. They range from mild to severe and include:

  • Pale or yellow skin
  • Feeling tired
  • Poor appetite
  • Dark urine
  • Enlarged spleen
  • Bone problems


The healthcare provider will ask about your child’s symptoms and health history. He or she will give your child a physical exam. Your child may also have tests, such as:

  • Complete blood count (CBC). This test checks the red and white blood cells, blood clotting cells (platelets), and sometimes, young red blood cells. It includes hemoglobin and hematocrit and more details about the red blood cells.
  • Peripheral smear. A small sample of blood is checked under a microscope to see if they look abnormal.
  • Hemoglobin electrophoresis. This test measures the types and amount of hemoglobin. 
  • Iron studies. These studies check for iron deficiency anemia.
  • DNA testing. These tests look for gene defects. DNA testing can find carriers.


Treatment will depend on your child’s symptoms, age, and general health. It will also depend on how severe the condition is.

Treatment depends on the type of alpha thalassemia.

  • There is no effective treatment for alpha thalassemia major. 
  • Most children with alpha thalassemia trait don’t need treatment. 
  • Most children with hemoglobin H disease don’t need treatment, but treatment may include:
    • A referral to a hematologist, an expert in blood disorders
    • Daily doses of folic acid, a vitamin vital to hemoglobin production
    • Blood transfusions may be needed if hemoglobin levels drop suddenly
    • Surgical removal of the spleen (rarely done)


Complications also depend on the type of alpha thalassemia. 

  • Most babies with alpha thalassemia major are stillborn or die soon after birth. 
  • Children with hemoglobin H disease may have delayed growth and development.

Complications from the treatment of hemoglobin H disease may occur. For example, 

  • A child has an increased risk of infection if he or she has spleen removed.
  • Iron overload may occur from frequent blood transfusions.

Living with

Your child should have his or her blood checked regularly. Talk with your child's provider about how often it should be checked.

Your child should also be checked if he or she has a fever. Fevers can cause a drop in hemoglobin.

Talk with the healthcare provider about having genetic counseling. 

When to Call a Healthcare Provider

Call your child's healthcare provider if he or she has:

  • Fever
  • Symptoms of anemia such as pale skin or tiredness

Key Points

  • Alpha thalassemia is an inherited blood disorder. It cause anemia. 
  • It’s caused by changes in the genes that control the production of hemoglobin.
  • The types are alpha thalassemia major, hemoglobin H disease, and 2 forms of alpha thalassemia carrier.
  • Treatment depends on the type of alpha thalassemia. Many children don’t need treatment.

Next Steps

Tips to help you get the most from a visit to your child’s healthcare provider:

  • Know the reason for the visit and what you want to happen.
  • Before your visit, write down questions you want answered.
  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you for your child.
  • Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.
  • Ask if your child’s condition can be treated in other ways.
  • Know why a test or procedure is recommended and what the results could mean.
  • Know what to expect if your child does not take the medicine or have the test or procedure.
  • If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your child’s provider after office hours. This is important if your child becomes ill and you have questions or need advice.