The purpose of this study was to assess diets of pregnant adolescents in Guam, including difference in age and trimester. The 434 subjects, aged 14 to 20 years, were primarily Chamorro and Filipino. Analysis of variance was used to determine differences in nutrient intake, and Tukey post hoc testing was used. Frequency distributions were calculated for intake at various dietary reference intake levels. Mean energy intake was 2,487±1,057 kcal. The nutrients that are inadequate in the diets of the adolescents are calcium, folate, vitamin E, magnesium, and iron. Calcium intake declined with increasing age (P<.0001). Notable differences (P<.01) among trimester existed only for iron, which was lower in the second than third trimester. Nutrient intake is similar to that in pregnant adolescents in the United States, with particularly low calcium levels. Culturally specific materials emphasizing nutrition during pregnancy and chronic disease prevention are warranted. J Am Diet Assoc. 2003;103:611-614.