Depression in women.

Depression is the leading cause of disease-related disability in women. Epidemiological studies have shown that the lifetime prevalence of a major depressive disorder in women (21.3%) is almost twice that in men (12.7%). This ratio has been documented in different countries and ethnic groups. Sex differences relating to depression vary with age, with male and female children showing similar incidence rates. National comorbidity data reveal that sex differences in prevalence first appear around the age of 10 years and persist until midlife, after which they disappear. Therefore, women have the greatest risk for developing depressive disorders during their child-bearing years. Several biological processes are thought to be involved in the predisposition of women to depression, including genetically determined vulnerability, hormonal fluctuations related to various aspects of reproductive function, and an undue sensitivity to such hormonal fluctuations in brain systems that mediate depressive states. Psychosocial events such as role-stress, victimization, sex-specific socialization, internalization coping style, and disadvantaged social status have all been considered to be contributors to the increased vulnerability of women to depression. Women are more susceptible than men to stress-induced depression and to changes in photoperiod (more than 80% of individuals with seasonal affective disorder are women). Depression in women may develop during different phases of the reproductive cycle (premenstrual dysphoric disorder, depression during pregnancy, postpartum depressive conditions, and menopausal depression). Other reproductive events such as infertility, miscarriage, oral contraceptives, and hormone replacement treatment have been reported to cause depression in women.