Depression is more common in women than in men as researchers have identified several gene variants linked to depression that occur only in women, including one that is related to female hormone regulation, a study said.

However, women acknowledge their symptoms while men are more reluctant to admit the problem or reach out for help.

Twice as many women as men are dealing with depression globally and one out of eight women have an episode of major depression at some time in her life, according to the May issue of the Harvard Mental Health Letter.

Women are also more vulnerable to bipolar disorder, seasonal affective disorder and dysthymia or long-term depression, the study said. The Harvard Mental Health Letter attributes women's increased susceptibility to various factors.

Some of the major factors are genetics, acknowledgment of symptoms, stress, premenstrual disturbances and pregnancy. Heredity accounts for up to 50 per cent of the risk for depression.

Women are more likely to say they are under stress, according to a survey of over 30,000 people in 30 countries.

Women, more than men, are subject to certain kinds of severe stress such as sexual abuse and domestic violence