Betty can’t get to sleep; Tashita can’t wake up. Nothing interests Mei Wu; Carmen cries when she’s home alone; and Lucy is convinced her life’s not worth living. They’re among the millions of women worldwide trying to cope with the symptoms of clinical depression.

Welcome to the blues sisterhood.

Rate Twice That of Males

Over the course of their lifetimes, 20 percent of all women are likely to find themselves in these women’s shoes, note Subahash C. Bhatia, M.D., and Shashi K. Bhatia, M.D. —a husband-and-wife team of professors at Creighton University School of Medicine in Omaha and University of Nebraska College of Medicine.

Writing in the July 1999 issue of American Family Physician, the Bhatias—both of them experienced psychiatrists&#151’point out that although the diagnostic criteria for depression is identical for both sexes, females experience the condition twice as often as males. The National Mental Health Association in Alexandria, Va., notes approximately 12 million women in the United States alone experience clinical depression each year.

A Global Disease Burden

Dr. Myrna Weissman of Columbia University’s New York State Psychiatric Institute and her colleagues reported a similar prevalence of depressive illnesses in women in the United States, Canada, Germany and New Zealand. Across the four nations, Weissman’s team identified double the rates of major depression and its milder form—known as dysthymia—in females compared to their male counterparts.

At the beginning of the 1990s, the World Health Organization named depression as the leading cause of “disease burden,” a measure of both illness and death, in women around the globe. But although medical science has taken giant steps forward in understanding the genetic and environmental bases of many common physical and mental ills, Bhatia and Bhatia say the exact reason for the wide gender gap in depression remains unknown.

The quest for an answer has researchers pursuing an interesting and ever-lengthening list of possibilities.

Depressing Combinations

Like other experts in women’s mental health, the Bhatias believe the higher prevalence of depression in women is probably due to a combination of gender-related differences in cognitive styles, certain biological factors, and a higher incidence of social, psychological and economic stresses in females. They list the following specific risk factors for women:

  • family history of mood disorders
  • personal past history of mood disorders in early reproductive years
  • loss of a parent before the age of 10
  • childhood history of physical or sexual abuse
  • use of an oral contraceptive, particularly one with a high progesterone content
  • use of gonadotropin stimulants for treatment of infertility
  • persistent psychosocial stressors (for example, job loss, family illness, poverty)
  • loss of a social support system or the threat of such a loss (for example, through a death, move, divorce)

Other researchers have delved more deeply into genetics and female biology to determine how these factors may relate to one another and which— if any—explain why so many more women than men get depressed.

An Inherited Trait?

Stress obviously plays a role in depression, but do women experience different stressors than men, or do they simply respond to the same stressors in a different fashion?

Researchers at the Medical College of Virginia looked for clues about how females react to environmental stressors in a study of more than 1,000 twin sisters, about half of whom had a family history of depression. According to the study’s director, Kenneth S. Kendler, M.D., a professor of psychiatry at MCV, recent exposure to a stressful event increased the risk of depression for the twins without a family history of the disorder only six percent. For twins who had such a family history, however, the risk was more than doubled, to 14 percent.

This suggests that women with a family history of depression may have inherited a tendency toward becoming depressed themselves, Kendler and his colleagues concluded. But, as the National Institute on Mental Health (NIMH) points out, not every woman with a family history develops the illness, while others with no such family history do.

Hormonal Factors

Hormones have attracted considerable attention as a likely cause for the huge differences between rates of depression in women and men. After all, women’s hormone-related reproductive events—including menstruation, pregnancy, the postpartum period, infertility and menopause—often are associated with mood fluctuations, including depression.

But in a National Institute of Health booklet, Depression: What Every Woman Should Know, U.S. government experts acknowledge that although female hormones do affect emotions and moods, the specific biological mechanism linking hormones such as estrogen to depression has yet to be identified.

The NIH further notes that some types of female depression, such as those that happen during the postpartum period or at the onset of menopause, more often occur in women who have had previous depressive episodes, even though they may not have been diagnosed or treated earlier. Other reproductive events—such as pregnancy and abortion—do not seem to result in a higher incidence of clinical depression. This knowledge has prompted study of the relationship between female hormones and depression from a different angle.

Estrogen May Set the Stage

Ellen Leibenluft, M.D., Chief of the Unit on Rapid Cycling Bipolar Disorder at the National Institute of Mental Health, explained in a June 1998 Scientific American article that “[I]t now appears that estrogen might set the stage for depression indirectly by priming the body’s stress response. During stressful times, adrenal glands—which set on top of the kidneys and are controlled by the pituitary gland in the brain—secrete levels of a hormone called cortisol. Cortisol increases the activity of the body’s metabolic and immune systems, among others. In the normal course of events, stress increases cortisol secretion, but these elevated levels have a negative feedback effect on the pituitary, so that cortisol levels gradually return to normal.”

“Evidence is emerging that estrogen might not only increase cortisol secretion, but also decrease cortisol’s ability to shut down its own secretion,” she added. “The result might be a stress response that is not only more pronounced but longer-lasting in women than in men.”

Such research is expected to provide part—but probably not all—of the explanation for the gender gap in depressive conditions.

Small Pieces, Complex Puzzle

According to Leibenluft, figuring out why depression is more common among women than men is difficult work and progress is necessarily slow. But, she added, “What is coming into focus is that certain environmental factors— including stress, seasonal changes and social rank— may produce different physiological changes in females than they do in males. These findings are small pieces in what is proving to be an incredibly complex puzzle.”

Additional Depression Resources Online

Need more information about women and depression? These websites and organizations may be helpful to you:

National Institute of Mental Health

6001 Executive Boulevard, Rm. 8184

Bethesda, MD 20892-9663

Telephone: (301) 443-4513


National Foundation for Depressive Illness, Inc.

P.O. Box 2257

New York, NY 10116

Telephone: (800) 248-4344


National Depressive and Manic-Depressive Association

730 N. Franklin St.

Suite 501

Chicago, IL 60610-3526

Telephone: (800) 826-3632 or (312) 642-0049


National Mental Health Association

1021 Prince St.

Alexandria, VA 22314-2971

Telephone: (800) 969-NMHA (969-6642)


Last reviewed:
On 13 Feb 2006
By John M. Grohol, Psy.D.