The purpose of the current study was to examine the influence of different maternal nutrition treatments during pregnancy on body weight, muscle fiber number, carcass traits, and pork quality traits of offspring. A total of 18 crossbred sows (Landrace${ imes}$Yorkshire${ imes}$Duroc) were randomly assigned to one of three nutritional treatment groups; control, high energy, and high protein. The control group was fed a standard diet, the high energy group was fed a diet that contained 30% increased metabolizable energy, and the high protein group was fed a diet that contained 30% increased limiting amino acids compared to the control. The sows in each group were fed equal quantities of each diet (1.9 kg/d) for the entire gestational period. A total of 36 piglets from each sow were used to evaluate changes in body weight, muscle fiber number in the longissimus dorsi muscle at birth, carcass traits, and pork quality traits. Birth weight of offspring born to sows in the high energy diet group was significantly higher compared to the high protein diet group (p<0.05). However, body weight of offspring after birth was not significantly different between the groups. Muscle fiber number for the longissimus dorsi muscle at birth was not significantly different between the groups. In addition, there were no significant differences in carcass traits or pork quality traits between offspring born to sows in the control group and those born to sows that received high energy or high protein diets during pregnancy. Based on these results, it appears that maternal nutrition treatment during pregnancy, regardless of whether it is with high energy or high protein diets, does not have a significant effect on body weight, muscle fiber number at birth, carcass traits, or pork quality traits.