Childhood Social Disadvantage and Pubertal Timing: A National Birth Cohort From Australia

BACKGROUND AND OBJECTIVES: Early pubertal timing is linked with a range of adverse health outcomes later. Given recent trends of earlier pubertal maturation, there is growing interest in the factors influencing pubertal timing. Socioeconomic disadvantage has been previously linked with reproductive strategies later in life. In this study, we aim to determine the association between cumulative social disadvantages in early life and early puberty in a population-based birth cohort. METHODS: Data are from the B (baby) cohort of The Longitudinal Study of Australian Children. Children (n = 5107) were aged 0 to 1 years when recruited in 2004 and 10 to 11 years (n = 3764) at Wave 6 in 2015. Household socioeconomic position (SEP) and neighborhood socioeconomic disadvantage were collected at all 6 waves. Trajectories of disadvantage were identified through latent class models. Early puberty at Wave 6 was assessed from parental reports using an adaptation of the Pubertal Development Scale. RESULTS: Cumulative exposure to extremely unfavorable household SEP in boys independently predicted a fourfold increase (odds ratio = 4.22, 95% confidence interval 2.27–7.86) in the rate of early puberty. In girls, the increase was twofold (odds ratio = 1.96, 95% confidence interval 1.08–3.56). We found no effect from neighborhood disadvantage once family SEP was taken into account. CONCLUSIONS: Cumulative exposure to household socioeconomic disadvantage in early life predicts earlier pubertal timing in both boys and girls. This may represent 1 mechanism underpinning associations between early life disadvantage and poor health in later life.