Yang Y, Wu F, Dwyer T, et al. - Given that early‐life exposures are associated with areal bone mineral density (aBMD) at ages 8 and 16 years, ascertained if these correlations persist into young adulthood when peak bone mass is achieved and extend this analysis to microarchitecture. Participants in the study were followed from the perinatal period to 25 years old (n = 201). Total body, spine, and hip aBMD (by dual‐energy X‐ray absorptiometry [DXA]), and cortical and trabecular bone measures at the distal radius and tibia (by high‐resolution peripheral quantitative computed tomography) were included outcomes. Breastfeeding, maternal smoking during pregnancy, and birth weight were early‐life exposures included. Breastfeeding was correlated with a lower risk of lower limb fractures and maternal smoking was related to deleterious upper limb fractures. Findings suggested that breastfeeding and maternal smoking may affect peak bone microarchitecture while subsequent growth counteracts the association with birth weight.