Anaemia in women: causes, symptoms and which blood values to test

Anaemia means you have too little haemoglobin, the red substance in your blood that carries oxygen around. As a result, less oxygen reaches your muscles and your brain, and you often feel tired or listless. In women, anaemia is relatively often the result of a shortage of iron.

This is the overview article in our series on anaemia and iron in women. I notice that many women hear their Hb or iron is low, but do not really know what those numbers mean. Below you will read what anaemia is exactly, why it is more common in women, which symptoms fit and which blood values you can test.

For the details per topic, see the separate articles in this series.

What is anaemia?

Anaemia, also called anemia, means the haemoglobin level in your blood is too low. Haemoglobin sits in your red blood cells and transports oxygen from your lungs to the rest of your body. With a shortage your organs and muscles get less oxygen, which can cause fatigue.

The World Health Organization usually speaks of anaemia in women when haemoglobin drops below roughly 120 grams per litre. The exact threshold differs per laboratory and per situation, for example during pregnancy. Your GP therefore always looks at the reference range listed with your result.

Important to know: anaemia is not a disease in itself, but a sign that something else is going on.

That can be a simple iron shortage, but sometimes there is another cause behind it. So it makes sense not to look only at your Hb, but also at values that can explain the cause. Further on in this article you read which values those are.

Why is anaemia common in women?

Anaemia is more common in women than in men, and that largely has to do with menstruation. With every period you lose blood, and with it iron. With a heavy or long-lasting period, that loss can be greater than what you replenish through food.

According to Thuisarts.nl, iron shortage is one of the most common causes of anaemia in women of childbearing age. Besides menstruation, a pregnancy and the period after birth also demand extra iron. That way your iron stores run down faster than you might think.

A heavy period is a cause that is easily overlooked.

Many women have got used to considerable blood loss and do not see it as anything special. Yet it is precisely that monthly loss that can slowly lower your iron stores. Read more about anaemia due to a heavy period and which values to test.

A diet low in iron can also play a part, for example with a vegetarian or vegan eating pattern. Iron from plant sources is absorbed less well than iron from meat. The Voedingscentrum therefore advises combining plant iron sources with vitamin C, which can improve absorption.

In addition, there are periods when your body simply demands more iron. Think of growth in puberty, or of breastfeeding after birth. In such phases an otherwise normal eating pattern can still provide just too little iron.

Finally, problems with absorption in your gut can play a role, although that is less often the cause. With certain bowel conditions your body absorbs iron or vitamin B12 less well. Whether this applies to you can only be assessed by your GP, based on your story and, if needed, further investigation.

What are the symptoms of anaemia?

The most common complaints with anaemia are fatigue, paleness, dizziness and being short of breath quickly on exertion. Headache, cold hands and feet, palpitations and concentration problems can also fit. The complaints arise because your tissues get less oxygen.

These symptoms are unfortunately not very specific. Fatigue and concentration problems fit dozens of other causes, from lack of sleep to a busy period. So blood testing is the only way to know for sure whether there really is anaemia.

Some complaints point a bit more towards an iron shortage.

Think of hair loss, brittle nails, a sore or smooth tongue, and sometimes a strange urge to chew on ice or non-edible things. These signals are not proof, but can be a reason to have your iron tested. A broader overview can be found in our article on recognising anaemia symptoms in women.

What stands out is that an iron shortage can cause complaints before your Hb actually drops. Your iron stores can already be low while anaemia is not yet visible. Read more about that at iron deficiency without anaemia and what a low ferritin means.

Which types of anaemia are there?

There are different types of anaemia, each with a different cause. The most common is anaemia due to iron shortage. In addition there is anaemia due to a shortage of vitamin B12 or folate, and there are forms linked to a chronic illness or a hereditary condition.

Doctors often classify anaemia by the size of the red blood cells, the so-called MCV. With an iron shortage the red blood cells are usually smaller than normal. With a shortage of vitamin B12 or folate they are often larger instead.

The MCV is therefore a handy first clue to the direction of the cause.

With a low MCV your GP thinks sooner of iron shortage, with a high MCV sooner of a vitamin shortage. This is not a hard rule, but a starting point for further investigation. Which values fit with this you can see in the table below.

A lesser-known cause is a shortage of vitamin B12, which can also cause complaints apart from anaemia. Think of tingling, forgetfulness or fatigue. Read more about the symptoms and testing at vitamin B12 deficiency symptoms and testing.

Which blood values do you test for anaemia?

To map anaemia and its cause, you usually look at a combination of values. Your Hb shows whether there is anaemia, while ferritin, iron and transferrin saturation say something about your iron stores. The MCV, vitamin B12 and folate help to determine the cause further.

The table below links each blood value to what it shows. The reference ranges differ per laboratory and per situation, so always read the value that belongs to your result and discuss it with your GP.

Ferritin is often the most interesting value for women, because it drops first with a creeping iron shortage. What a low or normal ferritin means exactly, you read in our article on the ferritin level, normal values and what a low ferritin means.

If you want to see the iron values side by side with their references, look in our iron values reference table with iron, ferritin and transferrin. That gives you a fuller picture than your Hb alone. Do remember that a table never replaces a conversation with your GP.

What can you do yourself about anaemia?

What you can do yourself depends strongly on the cause, so you want to know that first. With an iron shortage you can pay attention to iron-rich food, such as wholegrain products, legumes, green vegetables and, if you eat it, meat. Vitamin C with the meal can improve the absorption of iron from plant sources.

The Voedingscentrum emphasises that a varied eating pattern provides enough iron for most people. Yet that does not always work, for example with heavy blood loss or a limited diet. In that case your GP can prescribe or advise iron tablets.

Do not just start taking high doses of iron or vitamins yourself.

Too much iron can cause complaints and is not useful if you have no shortage. A B12 shortage is also better tackled in a targeted way than on a guess, because the cause differs per person. So always consult your GP before you start with supplements.

In women, menstruation often plays a role in the background. If a heavy period is the cause, then replenishing only helps temporarily as long as the loss stays large. Your GP can think along about the cause of the blood loss itself.

Patience is part of it too, because building up your iron stores takes time. Even with the right approach it can take weeks to months before your ferritin is back on track. A check of your blood values after a period of replenishing can show whether you are on the right path.

If you notice your hair thinning while your iron is low, there may be a link. Read how that works at iron deficiency and hair loss in women, the link and what to test.

Testing your own blood values

If you want to map your own iron and blood values, you can do so at Lunara without a referral. You order online, choose one of the more than 750 draw locations and have blood drawn in the morning. You get your results digitally, with an assessment by a BIG-registered doctor.

The Iron Status looks at your iron, ferritin and transferrin saturation, among other things, so you get a picture of your iron stores. If you also want to know your Hb and the size of your red blood cells, you look at a broader test that includes these values.

Testing yourself is meant as an addition, not as a replacement for the care of your GP.

You always discuss an abnormal result with a doctor, who looks at your whole situation. That way you know whether there really is anaemia and what the cause might be. Personally, I find that testing yourself is mainly valuable as a starting point for such a conversation.

Frequently asked questions

How do you know if you have anaemia?

You can only know for sure with blood testing, in which your haemoglobin (Hb) is measured. Complaints such as fatigue and paleness can be a clue, but are not proof. Your GP looks at your Hb in combination with other values.

What is the difference between iron shortage and anaemia?

An iron shortage means your iron stores are low, which you see in your ferritin. Anaemia only arises when your Hb becomes too low because of it. So you can have an iron shortage without anaemia yet.

Can a heavy period cause anaemia?

Yes, that happens regularly. With every period you lose iron, and with heavy blood loss that can be more than you replenish. Discuss with your GP whether your blood loss and your blood values need attention.

Which blood value drops first with iron shortage?

Usually that is ferritin, which reflects the size of your iron stores. Ferritin can already be low while your Hb is still normal. That is why ferritin is often a sensitive first value in women.

Can you have anaemia without complaints?

Yes, that is certainly possible. Some women have a slightly lowered Hb without clear complaints, especially if it has developed slowly. Blood testing then makes visible what you may not notice yourself.

Do I have to be fasting for an iron test?

For most iron tests you do not have to be fasting, but iron values can vary over the day. A morning draw therefore gives a more reliable picture. The draw location will let you know whether any preparation is needed.

References

1. NHG. NHG Guideline Anaemia. Dutch College of General Practitioners.
2. Thuisarts.nl. I have anaemia due to iron shortage. Dutch College of General Practitioners.
3. World Health Organization (WHO). Haemoglobin concentrations for the diagnosis of anaemia. WHO, 2011.
4. Voedingscentrum. Iron. Netherlands Nutrition Centre.

Every blood test result through Lunara includes a professional assessment by a BIG-registered doctor. Blood testing through Lunara does not replace a visit to your GP. For treatment decisions, discuss your results with your GP.