BRAIN STRUCTURAL LIFESPAN PATTERNS FROM MENARCHE TO MENOPAUSE

Across the female lifespan, hormonal fluctuations present periods of heightened neuroplasticity, alongside increased vulnerability to mental health disorders. Characterizing the brain structural changes across hormonal transition periods can provide novel insights into the neural foundations of women’s reproductive neuroplasticity and mental health. Using linear (mixed-effect) models applied on longitudinal and cross-sectional magnetic resonance imaging (MRI) datasets (ABCD and UK Biobank), we explored the effects of menarche onset (the beginning of the reproductive lifespan) and menopause onset (the end of the reproductive lifespan) on 68 cortical and 133 subcortical volumes. Cross-sectionally, 83 brain volumes showed menarche and 17 volumes menopause effects (P <.05 FDR-corrected). Of these, 7 brain volumes were affected by both transitional periods, showing opposing directional changes. Longitudinally, 56 brain volumes exhibited menarche effects, of which 46 replicated cross-sectionally. No longitudinal menopause effect survived correction for multiple comparison. Our findings confirm overlapping brain structural alteration between the two hormonal phases, suggesting a U-shape trajectory across the lifespan, and contribute to a better understanding of hormone related neuroplasticity. We next plan to extend our approach to a multivariate setting, applying machine learning models to classify menarche (pre vs post, age-matched) and menopause (pre- vs post-menopausal) based on brain anatomy. Applying these to other transition periods could allow us to contextualize changes underlying different hormonal transition periods against each other. This integrative framework aims to reveal overarching trajectories of neuroplastic changes across the female reproductive lifespan and shed light on potential neurobiological underpinnings of mental health vulnerabilities during key hormonal transitions.