Columbia University's Mailman School of Public Health Apr 13 2026 Higher levels of key steroid hormones-combined with elevated stress and body mass index (BMI)-are associated with earlier onset of puberty in girls, according to a new study at Columbia University Mailman School of Public Health. Many studies describe declining trends in the age at puberty, but until now few studies have examined how stress and BMI interact with a girl's hormonal biology. This paper is among the first to