This study aimed to establish a correlation between anthropometric and socioeconomic variables and repetition in school for first grade pupils, as well to determine the predictive value of such variables vis-à-vis repetition. A study with a prospective and concurrent approach was developed in four elementary schools in Belo Horizonte, Minas Gerais State, with 699 children (95% percent of those eligible). After adjustment for confounders, children whose mothers had less than eight years of schooling, of mothers with unskilled jobs, from single-parent households (mother, father, or guardian), whose per capita family income was less than or equal to half the minimum wage, and who had a height/age/sex index under the 10.1 percentile were at greater risk of repeating the first grade. The data are potentially useful for selecting children to be monitored and to prevent repetition in the schools investigated.