Polyphenols, the most abundant antioxidants present in the diet, are widely distributed in vegetable foods. One of the possible mechanisms to explain their activity is inhibition of synthesis and release of inflammatory mediators. However, clinical studies investigating the effect of polyphenols on inflammatory responses are inconclusive and, in most cases, only evaluate clinical outcomes. The role of polyphenols on the inflammatory response, and associated modifications of the plasma concentration of PGE2 in pregnant women, has not yet been studied.