Do Pregnant Women Need DHA Supplements?

Pregnant woman eating grapefruit.
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Question: Do pregnant women need DHA supplements?

Answer: Many pregnant women have questions about DHA (docosahexaenoic acid) supplements in pregnancy. This compound is not routinely found in regular prenatal vitamins. The polyunsaturated fatty acids (PUFAs) in the omega-3 and omega-6 families are needed for a healthy diet by everyone.

Derived mostly from plants, Omega-3 PUFAs have alpha-linolenic acid (ALA).

Fish oils are comprised of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The omega-6 PUFAs come mainly from whole grains, vegetables, eggs and cereals and contain linoleic acid (LA) and arachidonic acid (AA).

During the 3rd trimester, your baby's brain growth is at its peak. This is when these supplements were supposed to have had an effect. What seems to be more important is the ratio of the omega-3 and omega-6 fatty acids. For example, if you increase the omega-3 PUFAs, you may decrease the arachidonic acid (AA), an omega-6 PUFA, which may slow infant growth and development. DHA alone, without AA may also have negative side effects. Though it appears that real fish is what makes the difference and not artificial DHA.

This does not mean that the omega-3 PUFAs don't have a chance. In fact, some recent observational studies have shown that there may be a correlation in preterm birth, preeclampsia as well as hypertension in pregnancy with the Omega-3 PUFAs.

Women with a history of preterm labor had a 50% reduction in preterm labor rates with omega-3 PUFAs, though the general population did not seem to benefit. Though more quality studies are needed for all of these cases.

So before you buy supplements for yourself during pregnancy or feed supplements to your baby after birth, be sure to talk to your doctor or midwife about the potential benefits for you and your baby and how they may or may not outweigh the risks.

Remember, it's about a good ratio and timing. Because when all is said and done, no expert has the answer as to the appropriate amount or type of supplement that works well in pregnancy.


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