Iron and anaemia in pregnancy: what might be behind the tiredness?

Tiredness is very common in pregnancy and is often the result of hormones and a changing body rhythm. Sometimes iron deficiency lies behind it. This article explains why iron becomes more important and what you can do in daily life.

Why is iron more important in pregnancy?

Your blood volume rises noticeably in pregnancy. Your body makes more red blood cells to meet the needs of you, your baby and the placenta, and iron is needed to build haemoglobin, the part of red blood cells that carries oxygen.

Iron needs rise especially in the second and third trimesters. People whose iron stores were low before pregnancy may develop a deficiency more easily. This is not a failing; it is a natural response to your body's growing demand.

How can you tell if you are low in iron?

Symptoms may be mild or absent:

• Tiredness and weakness beyond what is usual for you
• Looking pale
• Getting out of breath easily, palpitations
• Dizziness or headaches
• Difficulty concentrating

These can have other causes in pregnancy, too. That is why routine blood tests are the reliable way. Haemoglobin is usually checked early in pregnancy and again later; your doctor interprets the results.

Sources of iron

Iron comes in two forms:

• Animal sources (haem iron): Red meat, chicken, fish. The body absorbs this form more easily.
• Plant sources (non-haem iron): Lentils, chickpeas, dried beans, spinach, molasses, dried apricots, raisins, whole grains.

If you eat vegetarian or vegan, combining plant sources with vitamin C and talking with your doctor about supplements can be especially helpful.

Habits that help or hinder absorption

• Help: Having something rich in vitamin C with an iron-rich meal; for example squeezing lemon over food, salad, peppers or an orange.
• Hinder: Tea and coffee can lower iron absorption. It is better to drink them an hour or two apart from an iron-rich meal.
• Milk and calcium supplements taken at the same time can also reduce absorption. If possible, having yoghurt and cheese at a different meal from your iron-rich main dish may help.
• Cooking in a cast-iron pan can raise the iron content of food a little.

Supplements: why under medical supervision?

If your blood tests show a deficiency, your doctor may suggest an iron supplement. A supplement is not something to start on your own: too much iron can upset the stomach, the same amount does not suit everyone, and it is adjusted according to test results.

Dark stools are expected while taking a supplement. Constipation and nausea can occur; your doctor may suggest a different way of taking it. Keep it out of reach of children.

What can you do?

1. Try to eat pulses and leafy greens a few times a week.
2. Add lemon or a piece of fresh fruit next to iron-rich meals.
3. Move tea and coffee to times away from meals.
4. Keep your routine blood test appointments.
5. On tired days, treat rest as a need, not an indulgence.

When to contact your doctor

• If you feel very pale, extremely tired or have palpitations.
• If you often feel dizzy or faint.
• If you are breathless even with light effort.
• If your haemoglobin came back low and you would like guidance on supplements or your diet.
• If you have any bleeding in pregnancy.

For chest pain, fainting or severe breathlessness, call 112 without delay.

This article is for information only; for your test results and any decision on supplements, your doctor's advice comes first.