Journal Article

Urban–rural disparities in menarcheal timing: a longitudinal cohort study examining social determinants of health (SDOH), screen time, and hormonal influences among adolescent girls in West Bengal, India

Zeyaullah, Md, Ahmad, S Rehan, Kumari, Anupriya

2026

Overview

Background This study aimed to evaluate the association between early menarche, lifestyle factors, screen time (TV and mobile phones) and psychological factors among girls aged 8–10 years living in West Bengal, India, with special emphasis on hormonal and psychosocial influences and an urban-rural perspective using the Social Determinants of Health (SDOH) framework. Method A mixed-methods cohort study of 1,200 girls (600 urban, 600 rural) was followed up over three years. Quantitative (hormone assays, anthropometrics) and qualitative (body image, screen use interviews) approaches were used to measure screen time, physical activity, sleep, diet, hormone levels (melatonin, cortisol, GnRH, LH, FSH, estradiol, leptin), anthropometrics (BMI, Tanner staging), and psychological outcomes (stress, anxiety, self-perception). Results Urban girls with > 4 h/day of screen time had ≈ 4.2 months earlier menarche onset than rural girls with < 2 h/day. In urban girls, early menarche was linked to increased cortisol, decreased melatonin, and increased estradiol, associated with greater sedentary activity and stress from social media. Rural girls exhibited resilience amid family stress. Urban girls had body image issues; rural girls used screens as a means of escape. Excessive screen time, hormonal interference, and growth accelerators, from increasingly worse urban diets to the exacerbation of inactivity and presenteeism, help explain the acceleration, which affects urban girls especially, given the activity-inactivity model & the potential for online bullying associated with a reliance on social media. Qualitative data elucidate the protective resilience of rural girls, constructing urban body dissatisfaction, rural escape mobility, and environmental contexts. Conclusion Our findings concluded that screen exposure accelerates menarche through psychobiological mechanisms, especially significant in urban-rural differences. To mitigate screen time effects and protect girls’ health across settings, context-specific interventions are critical. The SDOH framework highlighted how structural factors-like digital access, education stress, and community dynamics-shape puberty in meaningful ways.

• Publisher: BioMed Central,Springer Nature B.V,BMC
• Subject: 17β-Estradiol / Adolescence / Adolescent development / Adolescents / Biology / Biostatistics / Body image / Child development / Cohort analysis / Cortisol / Diet / Digital media / Early menarche / Environmental Health / Epidemiology / Exercise / Families & family life / Follicle-stimulating hormone / Girls / Gonadotropin-releasing hormone / Hormonal regulation / Influence / Leptin / Lifestyles / Longitudinal studies / Luteinizing hormone / Medicine / Medicine & Public Health / Melatonin / Menarche / Nutrition / Physical activity / Portable computers / Psychological factors / Psychosocial stress / Pubertal timing / Puberty / Public Health / Qualitative analysis / Quantitative analysis / Resilience / Rural areas / Rural urban differences / Schools / Screen time / Screen time exposure / Sex hormones / Social determinants of health / Social interactions / Social networks / System theory / Urban areas / Vaccine