Health Question

Should pregnant and breastfeeding women avoid some types of fish?

You can eat most types of fish when you're pregnant or breastfeeding.

Eating fish is good for you and your baby because it's a good source of many vitamins and minerals, as well as essential omega-3 fatty acids. 

But you should avoid eating some types of fish and limit the amount you eat of others.

Fish to avoid during pregnancy

When you're pregnant or trying to get pregnant, do not eat:

  • shark
  • swordfish
  • marlin

These types of fish contain high levels of mercury, which can affect your baby's developing nervous system.  

You should also avoid raw shellfish during pregnancy. For more information, read Can I eat shellfish during pregnancy?

Fish to limit during pregnancy


When you're pregnant or trying to get pregnant, you should limit the amount of tuna you eat because it also contains high levels of mercury.

Don't eat more than:

  • 2 tuna steaks a week (each weighing about 140g when cooked or 170g when raw), or
  • 4 medium-sized cans of tuna a week (about 140g a can when drained)

Oily fish

Pregnant women should also limit how much oily fish they eat because it contains pollutants such as dioxins and polychlorinated biphenyls (PCBs).

Don't eat more than 2 portions of oily fish a week.

You don't need to give up eating oily fish altogether, as the health benefits outweigh the risks as long as you don't eat more than the maximum recommended amounts.

Oily fish includes:

  • salmon
  • trout
  • herring
  • sardines
  • pilchards
  • mackerel

Other fish to limit during pregnancy

You should also limit how much you eat of some other fish that are not regarded as oily.

Don't eat more than 2 portions a week of:

  • dogfish (rock salmon)
  • sea bass
  • sea bream
  • turbot
  • halibut
  • crab

Research has shown that these might have similar levels of pollutants as oily fish.

Fish to limit during breastfeeding

When you're breastfeeding:

  • don't eat more than 1 portion of shark, swordfish or marlin a week (this advice is the same for all adults)
  • don't eat more than 2 more portions a week of oily fish

You don't need to limit the amount of tuna you eat while you're breastfeeding.

Fish you do not need to limit during pregnancy and breastfeeding

Fish are a good source of protein and contain many vitamins and minerals, as well as essential omega-3 fatty acids.

Adults are advised to eat at least 2 portions of fish a week as part of a healthy, balanced diet, at least 1 of which should be oily fish.

The same is true for women who are pregnant, trying to get pregnant or breastfeeding.

You don't need to limit or avoid other types of white and non-oily fish, such as:

  • cod
  • haddock
  • plaice
  • coley
  • skate
  • hake
  • flounder
  • gurnard

Read the answers to more questions about pregnancy.

Further information