It has been widely documented that there are gender differences in depression prevalence, with women experiencing major depression about twice as often as men. The lifetime risk of major depression in women is about 20% to 26%, compared to about 8% to 12% for men. This risk exists independent of race or ethnicity.
Several risk factors have been studied which might account for gender differences in depression prevalence:
- Sex Differences in Hormones: Given that the peak onset of depressive disorders in women coincides with their reproductive years (between the ages of 25 to 44 years of age), hormonal risk factors may play a role. Estrogen and progesterone have been shown to affect neurotransmitter, neuroendocrine and circadian systems that have been implicated in mood disorders. The fact that women often undergo mood disorders associated with their menstrual cycle, like premenstrual dysphoric disorder, also points to a relationship between female sex hormones and mood. In addition, the hormonal fluctuations associated with childbirth are a common trigger for mood disorders. Although menopause is a time when a woman's risk of depression declines, the periomenopausal period is a time of increased risk for those with a history of major depression. Other hormonal factors that may contribute to a woman's risk for depression are sex differences related to the hypothalmic-pituitary-adrenal (HPA) axis and to thyroid function.
- Gender Differences in Socialization: Researchers have found that gender differences in socialization could play a role as well. Little girls are socialized by their parents and teachers to be more nurturing and sensitive to the opinions of others, while little boys are encouraged to develop a greater sense of mastery and independence in their lives. This type of socialization is theorized to lead to greater depression in women, who must look outside themselves for validation.
- Gender Differences in Coping Style: Studies show that women tend to use a more emotion-focused, ruminative coping style, mulling their problems over in their minds, while men tend to use a more problem-focused, distracting coping style to help them forget their troubles. It has been hypothesized that this ruminative coping style could lead to longer and more severe episodes of depression and contribute to women's greater vulnerability to depression.
- Differences in Frequency of and Reaction to Stressful Life Events: Evidence suggests that, throughout their lifetimes, women may experience more stressful life events and have a greater sensitivity to them than men. Adolescent girls tend to report more negative life events than boys, usually related to their relationships with their parents and peers, and to experience higher levels of distress related to them. Studies of adult women have found that women are more likely than men to become depressed in response to a stressful life event and to have experienced a stressful event within six months prior to a major depressive episode.
- Social Roles and Cultural Influences: It has also been theorized that women who become housewives and mothers may find their roles devalued by society while women who pursue a career outside the home may face discrimination and job inequality or may feel conflicts between their role as a wife and mother and their work. Due to their social circumstances, adverse life events associated with children, housing or reproduction may hit women especially hard because they perceive these areas as important to their definition of themselves and may feel they have no alternative ways to define themselves when these areas are threatened.
Several researchers have also suggested that there may actually be no difference in prevalence between men and women. These researchers have proposed the idea that it may actually be that women seek help more often than men or report their symptoms differently, leading to them being diagnosed more often than men. However, other studies have refuted these claims.
Katz, Vern L. et. al., eds. Comprehensive Gynecology 5th ed. Philadelphia: Mosby, 2007.
Kornstein, Susan G. and Anita H. Clayton. Women's Mental Health: A Comprehensive Textbook New York: Guilford Press, 2002.
Piccinelli, Marco and Greg Wilkinson. "Gender differences in depression." British Journal of Psychiatry 177 (2000): 486-492.