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      21 Weeks pregnant

      Fish For Pregnancy

      21 Weeks pregnant

      Mega Omegas

      By the time you’re 21 weeks pregnant, your baby weighs more than your placenta. Their digestive system is starting to work and their bones are becoming harder and stronger. Learn how certain fats are important for their development at this time, and how to get a healthy serving of them in your daily diet.

      Foetus Pregnancy Week 21

      Your baby's development at 21 weeks

      Swallowing and experiencing taste in week 21 of pregnancy

      Weighing around 350g (just over 12oz), in week 21 of pregnancy your baby weighs more than the placenta. Their movements may be increasingly noticeable from now on as the cartilage in their body turns to bone, giving their limbs and joints more substance and strength.

      Your baby’s digestive system has started functioning at this stage, albeit in a simple way. One action thought to help their digestive system develop is swallowing amniotic fluid, which is also a source of nourishment for your baby. Naturally sweet, your amniotic fluid takes on subtle flavours of the food you eat each day, which your baby experiences thanks to their increasingly sensitive taste buds.

      Many of your baby’s activities can be seen on an ultrasound now, including swallowing and sucking their thumb. What you may never see is the fine hair called lanugo that covers their body until the later stages of pregnancy, when fat takes over the job of keeping them warm.

      Omega 3 and Omega 6 fats

      Omega 3 and 6 are two groups of fatty acids, including long chain polyunsaturated fatty acids (known collectively as LCPs). One of the Omega 3 LCPs is called docosahexaenoic acid, or DHA for short. During pregnancy, DHA contributes to your baby’s brain development and also supports the development of your baby’s eyes. It is also associated with development in infancy, contributing to the normal visual development of your baby throughout the first year.

      Include DHA in your second trimester diet to support the development of your baby’s brain and eyes.

      LCPs – a hot topic of research

      Experts have recently reviewed the evidence around the impact of LCPs in pregnancy. It’s been shown that taking extra DHA during pregnancy reduces the risk of preterm delivery and increases the birthweight of babies.

      For this reason, pregnant women are advised to include sufficient levels of Omega 3 fats in their diet, particularly DHA.

      A daily dose of healthy fats during pregnancy

      During pregnancy the HSE does not provide specific recommendations for an increase in Omega 3 fats, but they do acknowledge the importance of  including omega 3 rich foods in your diet. The best sources of DHA are oily fish like mackerel, sardines and salmon. However, experts advise limiting certain types of fish in pregnancy because of the levels of toxins they can contain. Supplements are available but it’s a good idea to talk to your midwife or GP to check if a supplement is necessary.

      For a healthy, safe intake, aim to eat 1–2 portions of oily fish per week. If you don’t like eating oily fish, be sure to include some other sources of Omega 3 fats in your diet such as nuts, seeds, dark green vegetables, rapeseed oil, wholegrain cereals and soya products. While your body can convert some of the Omega 3s in these foods into DHA, it is thought that this process is not very efficient, and they’re not a particularly good substitute for oily fish.

      Next steps

      Try these Omega 3 rich snacks and small meals:

      • Mackerel on a slice of wholegrain toast
      • Grilled salmon with steamed vegetables
      • Salmon fishcakes
      • A handful of nuts and seeds
      • A bowl of wholegrain cereal

      Your baby, this week

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      Questions about feeding and nutrition?

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      Your baby, this week

      Discover the science behind your baby's developments, week-by-week

      Join now for free

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