In the present study, we estimated the association between pregnancy glucose levels and offspring body mass index (BMI) z scores at 2, 3.5, 5, and 7 years of age, as well as z score trajectories across this age range, among Mexican-American women without diabetes or gestational diabetes. Beginning in 1999-2000, the Center for the Health Assessment of Mothers and Children of Salinas prospectively followed women from Monterey County, California (52 obese and 214 nonobese women) and their children. Plasma glucose values obtained 1 hour after a 50-g oral glucose load comprised the exposure. Offspring BMIs were compared with national data to calculate z scores. Increasing pregnancy glucose levels were associated with increased offspring BMI z scores at 7 years of age; a 1-mmol/L increase in glucose corresponded to an increase of 0.11 (standard deviation = 0.044) z-score units (P < 0.05). In nonobese women only, the mean z score over this age range increased with increasing glucose levels. The average BMI z score at 4.5 years of age increased by 0.12 (standard error, 0.059) units for each 1-mmol/L increase in glucose (P = 0.04). In obese women only, increasing glucose was associated with increases in BMI z score over time (P = 0.07). Whether interventions to reduce glucose values in women free of disease could mitigate childhood obesity remains unknown.