By Michaela Carrick

Essential fatty acids (EFAs) are long-chain, polyunsaturated fatty acids. They are needed by every cell in the body and are essential for overall health and development. EFAs can’t be made by the body and must come from the diet – through food or supplements. There are two main types of EFAs: omega-3 and omega-6. Both omega 3 during pregnancy and omega-6 play important roles in the growth and development of the fetus, especially in the development of their eyes, brain, and nervous system.

DHA and Foetal Development

One type of omega-3, Docosahexaenoic acid (DHA) appears to be an exceptionally important fatty acid in both the brain and eyes. DHA makes up 40% of the polyunsaturated fats in the brain and 60% of those in the retina of the eye15. Eating adequate amounts of omega-3 during pregnancy benefits the child in later life. Children whose mothers consumed enough omega-3 during pregnancy have been shown to have increased social skills and intelligence and decreased risk of cerebral palsy, autism and ADHD. 6,11,17.

The omega-3 fatty acid DHA and omega-6 fatty acid Arachidonic acid (AA) are essential for the growth and development of the fetus’ central nervous system1. AA is needed for communication between cells and cell division1. DHA is found at high levels in the brain and retina of the eye and plays a major role in eye and brain cell function4.

The third trimester of pregnancy is the peak growth period for the developing brain. During this time, the fetus collects approximately 50-70mg of DHA daily9.

Not only is DHA an important nutrient for the developing brain, but it has also been reported to play a role in the development of normal vision in infants. A study conducted in Canada investigated the effects of DHA supplementation during pregnancy on vision acuity in future life8. This study reported that female infants whose mothers consumed a DHA supplement during pregnancy were less likely to experience vision problems at 2 months of age than infants whose mothers did not consume a supplement8.

EPA and Fetal Development

Another omega-3 fatty acid, Eicosapentaenoic acid (EPA) can regulate the movement of DHA and AA across the placenta. Fatty acids can only travel across the placenta if they are bound to proteins called fatty acid binding protein (FABPs). Higher blood levels of EPA can cause an increase in the production of these proteins, allowing DHA to pass into the placenta and fetus. One FABP that is increased with high EPA levels, B-FABP is found in high amounts in developing brain cells of the fetus and strongly attracts DHA20. Essentially, EPA assists in DHA being transferred from the mother to the fetus.

A mother’s DHA intake and blood levels have been seen to have a major impact on the fetus’s blood levels8. This tells us that a mother’s intake of omega-3 during pregnancy is essential for normal development of the fetus. Insufficient EPA in the diet of a pregnant mother may limit the transport and uptake of this DHA. Since only a small amount of DHA can be converted to EPA, DHA supplementation alone is not enough to ensure optimal DHA blood levels in the growing fetus. 2,12,13. This further emphasizes the importance of increasing both EPA and DHA intakes during pregnancy.

Omega-3’s Effects After Pregnancy

Omega-3 intake during pregnancy has long-term effects on the development of the child. 11,875 pregnant mothers participated in a trial investigating the effects of fish consumption during pregnancy on markers of neuronal development7. This study reported that children born to mothers who had a high intake of fish during pregnancy had higher fine motor skill, social developmental and verbal intelligence scores compared to children whose mothers with lower fish intakes during pregnancy7.

As fish is a rich source of EFAs, particularly DHA, this trial highlights the importance of EFAs in fetal brain development and its effects on future cognitive ability. More recent research has reported that DHA supplementation can have similar effects on neuronal development, improving cognitive abilities later in life and reducing the rate of delayed cognitive development. 10,14.

Consuming omega-3 during and after pregnancy also has benefits for the mother, potentially reducing postpartum depression (PPD) and depression during pregnancy. PPD has negative effects on both the mother’s health and their child’s cognitive and emotional development2,3. Approximately 5-15% of all child-bearing women experience PPD1. The prevalence of PPD has been reported to correlate inversely with seafood consumption and the DHA content of breastmilk across population4.

Low intake of omega-3 is associated with the development of PPD5. There is also an association between maternal postpartum DHA status and the development of PPD6. Low intakes of omega 3 during pregnancy are commonly reported among pregnant women and new mothers and supplementation offer a safe and easy way to increase intakes. 7,8. DHA supplementation for 4 months post-delivery prevented the decline in DHA levels commonly reported in breastfeeding women but the rate of depression was unaffected9.

A higher dose and longer supplementation period of 8 weeks were seen to lower symptoms of PPD measured by the Hamilton Rating Scale for Depression (HRSD), the Edinburgh Postnatal Depression Scale (EPDS) and the Beck Depression Inventory (BDI) without any adverse effects10. Another study found similar results with a mean decrease in HRSD scores of 34% and a 41% decrease in EPDS scores after 8 weeks of daily omega-3 supplementation. 11.

It is recommended that all adults, including pregnant women, consume 2 servings of fish per week to reach their omega-3 requirement5. There is evidence that pregnant women do not reach this required intake. 3,16. It is crucial that pregnant women consume adequate omega-3 fatty acids as omega 3 during pregnancy plays a vital role in the growth and development of the fetus.

Although fish is a rich source of omega-3, pregnant women must avoid species high in mercury such as marlin, tuna, and swordfish which may have negative effects on the fetus5. Plant-based oils such as flaxseed oil, contain the omega-3 fatty acid α-linoleic acid (ALA). The issue with consuming only ALA products is that ALA is poorly converted to EPA and DHA making it impossible to depend on plant oils for adequate EPA and DHA during pregnancy2.

A high strength high purity omega-3 fish oil supplement offers a convenient and efficient method of meeting EPA and DHA requirements of omega 3 during pregnancy.

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