Date of Award


Document Type


Degree Name

Master of Public Health (MPH)


School of Public Health

First Advisor

Shiyi Wang


This study aimed to explore the association between body mass index (BMI) during adolescence and the risk of breast cancer in adulthood among a Chinese female population. We conducted a nested case-control study within a prospective cohort comprising 62,487 Chinese women aged 25-55 years. Adolescent BMI was retrospectively collected via interviewer-administered questionnaires and analyzed as the primary exposure variable. Breast cancer incidence served as the primary outcome. Propensity Score Matching (PSM) was employed to adjust for confounding variables, such as socioeconomic status, lifestyle factors, and adult BMI.Of the 9,163 participants eligible for analysis, 57 breast cancer cases were identified during the six-year follow-up. Preliminary analyses suggested a potential inverse relationship between higher adolescent BMI and later breast cancer risk. However, these associations did not reach statistical significance after adjusting for confounders using PSM. While an inverse trend between adolescent BMI and adult breast cancer risk was observed, the findings were not statistically significant, possibly due to the short follow-up period, limited breast cancer cases developed during follow-up, and limitations related to recall and social desirability biases. The study underscores the complexity of the relationship between early-life BMI and breast cancer, highlighting the need for longer-term studies with robust methodological designs to further elucidate this association.


This thesis is restricted to Yale network users only. It will be made publicly available on 05/07/2026