Nutrients for pregnancy


Did you know? Iron requirements are higher in pregnancy. Your body needs extra iron to ensure your baby has a sufficient blood supply and receives necessary oxygen and nutrients.

Iron supplements are not routinely offered to pregnant women because it has been increasingly recognised that the body becomes more efficient at absorbing iron as the pregnancy progresses. Without the loss of blood through monthly periods, you retain more of your body’s iron stores too.

However, it can be fairly common for women to develop iron deficiency during pregnancy so when you are pregnant you should eat plenty of foods containing iron. Iron is found in red meat (like beef and lamb), pulses, nuts, eggs, green leafy veg such as watercress, wholemeal bread, dried fruit and fortified foods such as breakfast cereals. Vitamin C helps your body absorb the iron from plant sources. So you will absorb more of the iron from a meal such as beans on toast if you have a glass of fruit juice with it. Tea or coffee can decrease the amount of iron your body absorbs from plant sources, so try not to consume these with meals.

Iron supplements may be recommended by your midwife or GP if the iron levels in your blood are found to be too low – ask your GP if you are worried about your iron levels.

Omega-3 fatty acids

Long chain omega-3 fatty acids, particularly decosahexanoic acid (DHA) found in oily fish (such as salmon, sardines and mackerel), are important for the development of your baby’s brain and eyes. However, pregnant women should eat oily fish in moderation with a maximum of 2 portions a week as oily fish can contain low levels of pollutants that can build up in the body. For guidance on how much and which type of fish you can eat, see table below.


Type of fish

Recommendation during pregnancy

Oily fish

Up to 2 portions* a week

Dogfish, sea bass, sea bream, turbot, halibut and crab

Up to 2 portions* a week

Other white fish

No limit

Cans of tuna

Up to 4 medium cans a week

Marlin, shark and swordfish

Do not eat

*A portion = 140g

Omega-3 fatty acids are good for a baby's development. So remember, don't give up eating oily fish (1-2 portions a week is great) but don't eat more than the recommended maximum. If you don’t eat oily fish you could try to look out for products fortified with omega-3 DHA, such as eggs. If you decide to take a supplement make sure that the supplement is suitable for pregnant women, as some fish oil supplements contain a high amount of vitamin A (such as cod liver oil), which you should avoid during pregnancy.


Calcium is really important for the growth and development of your baby’s bones and helps to maintain your bones.

Did you know? Calcium demands on the mother are high during the latter stages of pregnancy and during lactation. The skeleton of full-term infants contains 20–30 g of calcium, most of which is accrued during the last trimester of pregnancy. Nature is a clever thing and your body adapts so that it can absorb more calcium from the food you eat.

Dairy foods, such as milk, cheese and yogurt, are a great source of calcium so try to include these in your diet. Try to select low fat products, such as semi-skimmed milk and reduced fat cheese, where possible; they are still a great source of calcium. If you do not eat dairy foods, calcium can also be found in other foods, for example:

  • calcium-fortified soya and dairy-free alternatives (check the label)
  • calcium-fortified breakfast cereals (check the label)
  • canned oily fish with soft bones (such as canned sardines or pilchards)
  • some dark leafy green vegetables (such as kale, rocket, pak choi and watercress)
  • Some nuts and seeds – including almonds, brazil nuts, hazelnuts and sesame seeds

 For more information on the sources used in this text, please contact [email protected]

Last reviewed June 2015.