Anaemia in pregnancy

What is anaemia?

When you have anaemia, your blood doesn’t have enough healthy red blood cells or haemoglobin to carry oxygen around your body and to your baby.

Red blood cells are one type of cell in your blood. Their main role is to carry oxygen from your heart to the rest of your body — your brain, your muscles, your skin, your kidneys and everywhere else. Red blood cells are produced in bone marrow. They contain a protein known as haemoglobin, which is vital for carrying oxygen.

You need enough iron, vitamin B12 and folate to produce all the haemoglobin you need. If you don’t have enough of any of these nutrients, you may become anaemic.

What causes anaemia in pregnancy?

Your body changes during pregnancy, to look after your growing baby. Your body needs to make more blood when you are pregnant. On average, you will have about 5L of blood when you’re not pregnant, compared to 7 to 8L of blood near the end of your pregnancy.

Making the extra blood cells requires plenty of iron, vitamin B12 and folate to make all the extra haemoglobin needed. Iron deficiency is the main cause of anaemia during pregnancy. You need 3 times as much iron when you are pregnant than when you are not, and your iron requirements increase throughout the pregnancy.

Unfortunately, dietary iron is hard to absorb. This can make it difficult for your body to take in enough iron from the foods you eat, to make enough haemoglobin for your pregnant body’s needs. Because of this, many people become anaemic during pregnancy unless they take iron supplements.

Anaemia in pregnancy can also be caused by lack of folate (folic acid) and vitamin B12 in your diet, or by unusual bleeding, or by having a condition such as pre-eclampsia or sickle cell disease.

What are the symptoms of anaemia

Mild anaemia is common in pregnancy. If you have mild anaemia, you will feel a little tired. If you have severe anaemia, you may feel as if you are constantly out of breath. You may also feel weak, dizzy, irritable and find it hard to concentrate. You may experience palpitations (a fast heartbeat).

How is anaemia in pregnancy diagnosed?

You would usually have a blood test around the time you first see a doctor or midwife about your pregnancy; and again at 28 weeks to check your full blood count. Your haemoglobin level will be checked as part of this test. You might have further tests if your haemoglobin is low for your stage of pregnancy.

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How is anaemia in pregnancy treated?

If you are diagnosed with iron deficiency anaemia during pregnancy, your doctor may recommend iron supplements. Your doctor will continue to monitor your haemoglobin levels.

Some people who take iron supplements have side effects that include nausea or constipation. If you are finding it difficult to take iron supplements because of the side effects, or if your doctor sees that your haemoglobin levels aren’t rising even when you take the supplements regularly as prescribed, you may be offered treatment with intravenous iron (iron through your vein, also known as IV).

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What are the risks if I am anaemic while pregnant?

Being severely anaemic can affect your heart and make you more unwell if you lose a lot of blood during the birth.

How can anaemia in pregnancy be prevented?

There are 3 good ways to prevent anaemia during pregnancy:

• Start your pregnancy in good health.
• Eat well while pregnant.
• Take iron supplements if your doctor or midwife says you need to.

Starting pregnancy in good health

If you are thinking about becoming pregnant, you should see your doctor and get a check-up. At this time, you will get advice about anaemia and other conditions, and particularly about taking iodine and folate supplements.

People planning a pregnancy need to take a folic acid supplement for at least a month before becoming pregnant and continue this for at least the first 3 months of pregnancy. Taking folic acid supplements will decrease the risk of neural tube defects such as spina bifida. The standard dose is 0.5mg of folic acid per day. A higher dose may be recommended if you have diabetes, epilepsy, overweight or obesity or have had a child with a neural tube defect. Your doctor can recommend the correct dose for you.

It is also recommended to consume 150mcg iodine through supplements as well as having iodine as part of a healthy diet. Iodine is used in the body to produce thyroid hormones. It is essential for the baby’s development and if you are pregnant, you will need more iodine that the average person.

Eating well while pregnant

Eating a healthy diet helps to protect against anaemia. Iron is found in meats, iron fortified breads and cereals, eggs, spinach and dried fruit. Vitamin B12 is found in meat, fish, shellfish, eggs and dairy products. High levels of folate are found in green leafy vegetables, beans, muesli, broccoli, beef, Brussels sprouts and asparagus. Eating a diet rich in these foods will help prevent anaemia.

If you are vegetarian, you can replace animal foods with lentils, beans, tofu, eggs and soy drinks.

Eating plenty of citrus fruit and avoiding tea and coffee with or soon after meals, may help you absorb the iron in your food, and may help prevent anaemia.

Supplements

If you are planning a pregnancy, ask your doctor or pharmacist to recommend an iodine and folate supplements before pregnancy and for the first 3 months. Your health team may also recommend that you take iron supplements if your blood tests show that you are iron deficient or are at risk of becoming iron deficient.

Vegetarians and vegans may be advised to take vitamin B12 supplements. If you are considering taking supplements, talk to your doctor or dietitian about the best ways to take them, and how to avoid any possible side effects.

Resources and support

Nutrition Australia also provides fact sheets on iron rich foods.

The Thyroid Foundation provides advice on iodine supplementation.