Brix N, et al. - In this population-based cohort study, researchers examined the possible relationships between maternal smoking during pregnancy and pubertal development in sons and daughters in 15,819 children from the Danish National Birth Cohort who were born 2000-2003. Between 2012 and 2017, provided half-yearly information on puberty from the age of 11 years. The investigators estimated adjusted age differences (in months) at attaining various pubertal milestones. They found that smoking in pregnancy was related to earlier genital development, pubic hair development, and voice break in sons, and earlier breast development, pubic hair development stage 3 to 5, and first menstrual period in daughters. These findings indicated that fetal exposure to tobacco smoke might advance the timing of puberty in boys and girls.