One in five women can expect to develop clinical depression during their lifetime. Regardless of age, race, or income - clinical depression can occur in any woman, and can be serious enough to lead to suicide.

Many people understand that clinical depression causes sadness and withdrawal. But depression can also cause anxiety, irritability, fatigue and changes in eating and sleeping habits. Depressed people often feel worthless or hopeless, and may experience physical symptoms as well, including chronic pain.

Women are more than twice as likely as men to experience clinical depression. Although all the reasons for this difference are not known, research suggests that biological differences in women - such as hormonal changes and genetics - may contribute to depression. Additionally, social reasons, such as greater stresses from work and family responsibilities, the roles and expectations of women, and even the increased rates of sexual abuse and poverty among women may lead to higher rates of clinical depression.

Despite the number of women who experience clinical depression, it is, in fact, not a "female weakness" or simply a normal part of being a woman. The good news is that clinical depression is a very treatable medical illness. Women with clinical depression need to know that successful treatments are available.

Clinical depression is more than "the blues," which we all experience now and then. It is normal to feel sadness or upset at times of the death of a loved one, from a divorce and in times of illness. Too much work or troubles at home can be stressful. But, most women can go through these difficult times without becoming clinically depressed.

Some people incorrectly believe that only those who have experienced depression for months, or who have completely lost their ability to function, have clinical depression. In fact, when the symptoms of depression last more than two weeks, or when the symptoms are severe enough to interfere with daily life, you may have clinical depression.

While we do not know all the reasons for this, research indicates the following:

Adolescence

The higher incidence of depression in women begins in adolescence, when there are dramatic changes in roles and expectations for teenage girls, along with physical and hormonal changes.

Adulthood

Many women face a variety of stresses, such as major responsibilities at home and work, a greater likelihood of being a single parent, and caring for children and aging parents. Rates of depression are highest for women when they are unhappily married. Being unmarried, including being separated or divorced, increases depression in both women and men.

Menstruation and Premenstrual Syndrome

While many women experience irritability or depressed feelings before their menstrual period, caused by changes in hormone levels, these feelings usually last only a few days. Extreme emotional and physical symptoms are called premenstrual syndrome (PMS) and may benefit from treatment by a doctor.

Postpartum Depression

Many women experience sadness following childbirth, ranging from a few days of the "blues" to clinical depression. Although as many as one out of every ten new mothers experience serious depression, in most cases it passes in a week or two. However, long-lasting clinical depression in a mother can have a negative effect on a child's behavior and development, which is another very important reason to seek treatment.

Menopause

Women are at no greater risk for clinical depression during menopause than at other times in their lives. However, women who have a history of clinical depression may be more likely to experience a recurrence during menopause.

Late Life

Some factors in later life can increase the risk of clinical depression. The death of a spouse may lead to depression. Additionally, clinical depression can be triggered by other illnesses including heart disease, cancer, diabetes and arthritis. Called "co-occurring depression," it should be treated in addition to treatment for the other illnesses. Depression is never a normal part of growing older.

How these factors affect women is not yet fully understood. Regardless of the reasons, depression is not a normal part of a woman's life.