Anaemia During Pregnancy
During pregnancy, your iron needs increase significantly. Iron is an essential mineral your body needs to make haemoglobin, the protein in red blood cells that carries oxygen to other cells in your body. Your growing baby also needs iron, and will store it for use in the first six months of life outside the womb. Therefore it's really important to try to prevent anaemia during pregnancy.
In this article, we’ll cover everything you need to know about anaemia during pregnancy – from signs and symptoms to why it can happen. Firstly, a little on why iron is so important to your body.
Why Is Iron So Important?
Iron is primarily absorbed through the intestine.
Once it's absorbed, a protein called transferrin carries iron around the body and into the bone marrow, to make red blood cells.
Haemoglobin is the protein in blood cells that gives blood its red colour. Oxygen, which is necessary for all cells to live and carry out their functions, attaches itself to haemoglobin. If the bone marrow does not make enough haemoglobin then the red blood cells will be unable to provide enough oxygen in the body.
Transferrin passes iron over to another protein called ferritin. Ferritin acts like a holding tank for iron and is usually found in large amounts in the brain and liver. We often hear ferritin referred to as ‘stored iron’, as it is the back up supply the body relies on if, for some reason, there isn’t enough iron circulating in the body .
Normal Low Iron During Pregnancy
During pregnancy your body produces more blood. In the second half of pregnancy you will have up to 50% more blood volume. During this time it is normal for your haemoglobin levels to go down as the red blood cells can’t increase fast enough to keep up with the higher volume of blood. If you have enough stored iron (ferritin), then you won’t notice many, or even any, physical effects of lower haemoglobin levels.
However, if you don’t have enough red blood cells and stored iron to meet the increased demand pregnancy makes on your body, you could become anaemic. Left untreated, severe anaemia can increase your risk of serious complications like preterm delivery and low birth weight in your baby. It's also associated with a higher risk of stillbirth or newborn death.
If you lose a lot of blood during birth, anaemia might cause you problems such as dizziness, and increased heart rate; you might even need a blood transfusion. Research indicates iron deficiency anaemia can also make women more susceptible to postpartum depression.
Signs of Anaemia During Pregnancy
Anaemia is a problem with the number and quality of red blood cells in your body. Some women might not experience any, or only some, of the following symptoms of anaemia when pregnant:
- Pale skin (especially fingernails, inside of eyelids, and lips)
- Tiredness to extreme fatigue
- Feeling of weakness
- Changes in blood pressure when standing up
- Frequent headaches
- Heart palpitations
- Difficulty concentrating
- Cracked or red tongue
- Loss of appetite
- Cravings for non-food substances (pica).
Many of these symptoms seem common to pregnancy but can be a sign that your iron levels are too low.
Can I Prevent Anaemia During Pregnancy?
The best way to prevent anaemia is to ensure you are covering all the nutritional bases – before you become pregnant and during your pregnancy. Most women hear ‘iron rich food’ and automatically think this means having to eat red meat at every meal. There are many ways to include iron rich foods in your diet that aren’t animal-based.
Haeme iron is found in animal foods that originally contained haemoglobin, such as red meats, fish, and poultry. Iron is highly available in offal foods such as liver, but be aware that offal is high in Vitamin A. High levels of Vitamin A have been linked to birth defects, but it does help to release stored iron, so not enough can lead to iron deficiency. Your body absorbs up to 25% of the iron in haeme sources.
Non-haeme iron comes from some animal-based food and from plant sources. These include eggs, spinach, kidney beans and lentils, dried apricots, blackstrap molasses, almonds, and iron fortified cereals. Less than 5% of iron from non-haeme sources is absorbed. Eating vitamin C rich foods with non-haeme sources can improve absorption of the available iron.
Some foods can reduce your body’s ability to absorb iron:
- Soy can reduce absorption from plant sources
- Coffee, tea and wine contain tannins, which bind to iron and carry it out of the body
- Wholegrains include phytates and fibre, which reduce the absorption of iron and other minerals
- Calcium and phosphorus reduce absorption of iron. It is not recommended to have iron supplements with milk.
Studies have shown that women with normal blood values don’t receive any health benefits from taking 30mg of iron daily, although the risks of anaemia are lowered. Most prenatal vitamins contain iron as part of the overall nutritional intake.
If you suspect you have iron deficiency anaemia, speak to your care provider, who can order a full iron blood test to assess your haemoglobin, ferritin and transferrin levels. This provides a full overview of iron levels in your blood, iron storage, and your body’s capacity to absorb iron; it will also help determine the best way to manage your symptoms.
Which Iron Supplement?
When your body is already low in iron, and anaemic, it can be difficult to get enough iron back into the body, even if your diet is high in iron. Most care providers will prescribe oral iron supplements for mild to moderate anaemia, with a daily dosage of 60–120mg of elemental iron.
Elemental iron is the total amount of iron in the supplement available for absorption by your body. You might notice that iron supplements have different types of iron in them. Each type has a different percentage of elemental iron and this can affect how much of the supplement you need to take.
For example, Spatone, a popular liquid iron supplement, has only 5mg of elemental iron, compared with other supplements that have 100mg of elemental iron. Iron supplements that have little elemental iron are useful for maintaining normal iron levels but have little impact on replacing iron in severely deficient women.
It’s important to note that oral iron supplements are not a ‘one size fits all' treatment and some forms can cause constipation and digestive upsets. Higher doses of iron can also cause nausea and vomiting. You might need to try a few forms of iron before finding one that is best for you. Liquid forms are usually tolerated much better, but practitioner-only brands (from naturopaths) are often much gentler on the stomach.
For some women, supplements work quickly, and they will start to feel better within a few weeks. Others might not notice any difference and might need to change supplements to find one that works best for them.
If you have malabsorption disorders or severe anaemia, you might require iron supplementation, via injection or infusion (IV drip). This is usually reserved as a last resort, or if you are very close to giving birth and oral supplementation will not have time to increase your iron levels.