Omega-3 Fatty Acids
Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are key omega-3 fatty acids (O3FA). Maternal intake of these fatty acids during pregnancy and breastfeeding delivers multiple benefits for mother and baby (table 1 below). The main dietary source is seafood, and particularly cold-water ocean fish. Consumption of this and/or fish oil supplementation is the easiest way to obtain both DHA and EPA. The best plant sources of O3FA include flaxseeds, walnuts, soybeans. For women who do not eat much fish, O3FA from fish oil supplementation can be an effective way to address low levels. Check supplement labels to ensure the specific listing of DHA and EPA.
Before conception: The typical American diet has many deficiencies, including low intake of ocean fish. The NIH recommended intake is 220 mg/d each of DHA and EPA. This is increased to 300mg/d of DHA in pregnancy. So, encourage your patients to try to achieve this so they are not at a disadvantage in their overall nutrition prior to becoming pregnant.
During pregnancy: Mothers will lose up to 50% of their O3FA stores, and it takes an average of 6m to recover the deficit created during pregnancy and lactation. Deficiencies of O3FA may be a contributing factor for severe complications in pregnancy and postpartum.
Table 1: Benefits of prenatal supplementation with omega-3 fatty acids (DHA and EPA)
(zimpenfish, Alien fish oil, flickr, flickr. CC: BY 2.0. Downloaded on August 3, 2009.)
Concerns regarding mercury toxicity:
Fish is an important source of O3FA, but there is concern regarding the mercury content of some fish. Fish farmed from the great lakes are thought to not be safe during pregnancy. There are variations in mercury content of different fish species.
Useful websites:
http://www.epa.gov/waterscience/fish/advice/
http://www.nrdc.org/health/effects/mercury/protect.asp (contains downloadable PDF pocket card)
http://www.americanpregnancy.org/pregnancyhealth/fishmercury.htm