Psychosocial Stress Trajectories are Associated with Puberty Timing: Findings from A 7-year Cohort in Chongqing, China.

Objectives: To evaluate the association between psychosocial stress (PS) trajectories and pubertal outcomes of girls and boys in a Chinese cohort (2015-2022).

Methods: Pubertal outcomes of 732 girls and 688 boys were physically examined every 6 months. Stressful life events were repeatedly assessed 7 times. Group-Based Trajectory Model was fitted for the optimum trajectories of total PS and PS from 5 sources. Cox model adjusted for age, BMI and socioeconomic factors was used to evaluate the association.

Results: Compared to the "low, gradual decline" trajectory, the "moderate, gradual decline" trajectory of total PS was associated with late menarche (HR: 0.816, 95% CI: 0.677-0.983), late pubic hair development (HR: 0.729, 95% CI: 0.609-0.872) and late axillary hair development (HR: 0.803, 95% CI: 0.661 - 0.975) in girls. Girls following the "high, rise then decline" trajectory of PS from family life demonstrated delayed axillary hair development (HR: 0.752, 95% CI: (0.571-0.990). As for boys, the "high, rise then decline" trajectory of PS from academic adaptation (HR: 0.670, 95% CI: 0.476 - 0.945) and life adaptation (HR: 0.642, 95% CI: 0.445 - 0.925) was associated with late axillary hair development. Boys in the "moderate, gradual decline" trajectory of PS from peer relationship was at risk of early testicular development (HR: 1.353, 95% CI: 1.108 - 1.653).

Conclusions: Chronic PS may be associated with delayed onset of several pubertal signs in both girls and boys. It may also accelerate testicular development of boys, indicating its varying impact on pubertal timing during early and later stages.