The constant ebb and flow of hormones that guide the menstrual cycle don't just affect reproductive anatomy, they also reshape the brain. But, not just the areas associated with reproduction (hypothalamic-pituitary-gonadal-axis (HPG-axis) receptor-dense regions). The microstructure of white matter – the fatty network of neuronal fibers that transfer information between regions of gray matter – has been found to change with hormonal shifts (puberty, oral contraception use, gender-affirming hormon