It has long been noticed that women are over-represented in the group of sufferers from depression. In most studies they consistently appear to outnumber their depressed male counterparts by a ratio of two to one. By contrast, the number of men and women seeking treatment for depression is roughly equal.

It may be that women are more readily detected as depressed than men. Women generally have more extensive networks of social supports and confidants, which has been shown to be an effective source of help for those with depression: men, who are relatively lacking in this resource, may more readily turn to professionals for help.

Finally, it may be true that women are more likely to suffer from depression, either because of inherent constitutional reasons (though there is no evidence to support this view) or because of their relative social disadvantage. In addition there are experiences, like the menstrual cycle or pregnancy, that by nature are restricted to women.