Composite Assessment of Menstrual Irregularity and Its Determinants Among Medical and Non‐Medical Female Undergraduates in Chittagong, Bangladesh: A Cross‐Sectional Study

Background and Aim: Menstrual irregularities affect women's physiological, psychological, and reproductive health, yet remain understudied among university students in Bangladesh. This study aimed to assess menstrual characteristics using a composite menstrual irregularity (CMI) score and identified key determinants among female undergraduates in Chittagong. Methods: An institution-based cross-sectional study was conducted among 469 female undergraduates from three universities in Chittagong, Bangladesh (September 2024-May 2025). The CMI score and Perceived Stress Scale (PSS-10) were used for assessing menstrual irregularity and stress level respectively. Multivariable logistic regression models have been applied; results are shown as adjusted odds ratios (AORs) with 95% confidence intervals (CIs). Results: = 0.023). High perceived stress was not independently associated with any threshold. The Internet and mass media were the primary sources of menstrual knowledge (52.5%). Conclusions: Menstrual irregularity is prevalent and multidimensionally patterned among female undergraduates in Bangladesh. Perceived stress, though elevated among non-medical students, was not independently associated with irregularity in adjusted models. Metrorrhagia, income, late menarche, and living arrangements are key modifiable factors. These findings support targeted university health interventions and evidence-based menstrual health policies in Bangladesh.