The Effects of Breastfeeding Duration on Children's Behavior Problems at Around Three Years of Age

Lu Gao¹Jianhui Yang^2*Esben Strodl³Chuan-an Wu⁴Xiao-Na Yin⁴Guo-Min Wen⁴Deng-Li Sun⁴Danxia Xian⁴Wei-Qing Chen^5,6*

• ¹Hangzhou Lin’an District Centre for Disease Control and Prevention (Hangzhou Lin’an District Health Supervision Institute), Hangzhou, China
• ²Ningbo Municipal Center for Disease Control and Prevention, Ningbo, China
• ³Queensland University of Technology School of Psychology and Counselling, Kelvin Grove, Australia
• ⁴Women’s and Children’s Hospital of Longhua District of Shenzhen, Shenzhen, China
• ⁵Department of Epidemiology, School of Public Health, Sun Yat-sen University, Shenzhen, China
• ⁶Department of Information Management, Xinhua College, Sun Yat-sen University, Guangzhou, China

Background: Although breastfeeding has been demonstrated to benefit children's health in the initial stages, the lasting effects on behavioral development throughout childhood remain unclear. This study explored the associations of exclusive and overall breastfeeding duration with behavioral problems in Chinese children, aiming to establish evidence-based recommendations for their prevention and management. Methods: A cross-sectional study involving 17,867 three-year-olds in Longhua District, Shenzhen, China, used questionnaires on socio-economic status, breastfeeding patterns, and behavioral problems. Breastfeeding durations were analyzed as continuous and categorical variables. Logistic, linear regressions, and spline plots were used to assess relationships. Results: Among 17,867 children, 14.3% had behavioral problems. Exclusive breastfeeding for the first 6 months was significantly associated with lower psychosomatic problem scores. Duration of exclusive breastfeeding exhibited a L-shaped relationship with behavioral problems. Breastfeeding for ≥13 months compared to ≤6 months was linked to a lower risk of behavioral problems, including impulsive-hyperactivity, and lower scores for learning, psychosomatic problems. A linear relationship was observed between total breastfeeding duration and behavioral problems. Conclusions: Adequate exclusive breastfeeding and extended breastfeeding could reduce behavioral problems in Chinese children, but causal directionality of observed associations remains undetermined due to cross-sectional data. Given alignment with current breastfeeding guidelines, interventions to extend breastfeeding duration may help mitigate childhood behavioral problems. Further cohort studies are needed to confirm causality and understand long-term impacts.