We have investigated the hypothesis that stress condition will accelerate pubertal maturation in adolescent girls and that faster maturing girls will display more behavioral problems than their on-time or late-maturing peers during pubertal development. Longitudinal data were collected yearly from 1986 to 1997. Parents of 1039 French-speaking Canadian girls completed a questionnaire about their characteristics as well as those of their family. To predict onset of puberty by time and cumulative risk factors, a Hierarchical Regression Analysis and a Survival Regression Analysis were conducted. Results revealed that: (1) anxiety at 8 years old, lower level of anxiety a year earlier and more adverse family condition predict a younger age at first menses; and (2) Body Mass Index, conflicts, and sleep disturbances significantly predict the onset of puberty. Complementary standard regression analyses demonstrated that situational stress mediated the effect of these variables. We concluded that precocious puberty could be an indicator of stress in a child, thus, allowing professionals to intervene early and to prevent later problems in psychosocial adjustment.