Iron in pregnancy

Your body needs iron to make red blood cells for both you and your baby. If you are anaemic, or are having twins, your doctor may give you iron supplements in pregnancy.

Iron is needed for healthy red blood cells for both you and your baby. Red blood cells carry oxygen around your body to your organs and tissues, as well as to your baby. 

In pregnancy, the amount of blood in your body increases by almost 50%. Some women become short of red blood cells, which is called anaemia. If you are anaemic, you may lack energy and feel very tired. Your doctor or midwife will find out whether you have anaemia through your routine antenatal blood tests. If you are having twins or multiple babies, you are more likely to be low in iron. 

If your blood tests show that you are anaemic, your doctor or midwife will give you an iron supplement. If you do not have anaemia, you do not need to take an iron supplement. 

Iron supplements can cause some side effects, like stomach pain, constipation and your poo may be black. Find out more about taking iron supplements.

Getting iron from your food 

Most people should be able to get all the iron they need by eating a healthy, balanced diet. Some food has more iron than others. 

The follow foods are all good sources of iron: 

  • red meat, oily fish and eggs
  • green leafy vegetables such as broccoli or spring greens
  • beans, such as red kidney beans, black-eyed peas, baked beans and chickpeas
  • soya beans and soya products, such as tofu
  • nuts and dried fruit, such as dried apricots
  • wholemeal bread and fortified breakfast cereals.

Foods to help the body absorb iron

As well as choosing foods that contain iron, it is important to make sure you are eating foods that help iron get absorbed into your body. Some foods and drinks also stop iron from being absorbed, so it is important to be aware of these too. 

Fruits and vegetables containing vitamin C can help the body absorb iron. These include:

  • kiwi fruit
  • oranges
  • potatoes
  • cauliflower
  • broccoli
  • brussels sprouts
  • parsley. 

Drinking tea and coffee (including decaf versions) can stop iron being absorbed into your body, especially drinking them with a meal. It is important to cut down on your caffeine intake in pregnancy anyway, find out more about caffeine and pregnancy

Crawley, Helen. (2017) Eating well for a healthy pregnancy: A practical guide. Second edition. Published by First Steps Nutrition Trust.

Hoppe M, et al. (2013). “Heme iron-based dietary intervention for improvement of iron status in young women.” Nutrition 2013;29:89-95

Hunter S, Robson (1992) SC Adaptation of the maternal heart in pregnancy Heart ;68:540-543.

Macdonald S, Magill-Cuerden J (2012) Mayes’ Midwifery, 14th edition, London, Ballière Tindall

National Institute for Health and Care Excellence (2010) ‘Antenatal Care’, NICE Clinical Guidelines 62

NHS Choices (accessed 28/10/20) Iron:

NHS Choices (accessed 12/11/2014) Supplements in pregnancy:

NHS Choices (accessed 28/10/20) Your healthy twin pregnancy:

Review dates
Reviewed: 04 March 2021
Next review: 04 March 2024

This content is currently being reviewed by our team. Updated information will be coming soon.