Sex Differences in Stress Susceptibility as a Key Mechanism Underlying Depression Risk.

Using the Social Signal Transduction Theory of Depression as a theoretical framework, women's elevated risk for depression may stem from a tight link between life stress, inflammation, and depression in women. Further, research finds hormonal contraceptive use alters cortisol and inflammatory reactivity to acute stress in ways that may increase depression risk in females. Finally, beyond established epigenetic mechanisms, mothers may transfer risk for depression to their female offspring through stressful family environments, which influence stress generation and stress-related gene expression. Together, these findings provide initial, biologically plausible clues that may help explain the relatively greater risk for depression in females vs. males. Looking forward, much more research is needed to address the longstanding underrepresentation of females in biomedical research on the biology of stress and depression.