Methylmercury crosses the placenta and increases the risk of impaired neurodevelopment in the fetus. Federal guidelines for fish intake and fish advisories are in place to help people of all ages limit their exposure to mercury from fish. However, recent studies suggest that the awareness of fish advisories is low among women of childbearing age. Fish intake is strongly correlated with hair mercury concentrations. In women in states with fish advisories, hair mercury concentrations were 7-fold higher in women who consumed 20 or more servings of fish than in those who reported nofish consumption in the past 3 months (0.59 vs. 0.08 microg/g). Among this high fish consumption group, the 75th and 95th percentile of hair mercury concentrations were 0.99 and 2.29 microg/g, respectively. This is of concern because the US Environmental Protection Agency (EPA) recommends that hair mercury be less than 1 microg/g. Public health campaigns to reduce mercury exposure need further refinement to reach women of childbearing age.