Depression can be described as feeling sad, blue, unhappy, miserable, or down in the dumps. Most of us feel this way at one time or another for short periods. But true clinical depression is a mood disorder in which feelings of sadness, loss, anger, or frustration interfere with everyday life for an extended time. Depression can be mild, moderate, or severe. The degree of depression, which your doctor can determine, influences how you are treated.

Around ten to twenty percent will experience major depression symptoms following the birth of their child. These symptoms--anxiety, irritability, insomnia, feelings of guilt, difficulty concentrating, persistent weepiness or sadness--are persistent and intense as compared to the milder "baby blues". Onset of symptoms is usually within the first six weeks antepartum. These symptoms can last a year or even longer, although three to six months is the average. Hormones are also thought to play a role in this type of postpartum depression, but family and patient history of depression, lack of support and negative life events are risk factors as well. Postpartum depression responds well to antidepressants and therapy.

A form of severe depression after delivery that requires treatment. It is sometimes said that postpartum depression (PPD) occurs within 4 weeks of delivery but it can happen a few days or even months after childbirth. A woman with PPD may have feelings similar to the baby blues -- sadness, despair, anxiety, irritability -- but she feels them much more strongly than she would with the baby blues. PPD often keeps her from doing the things she needs to do every day. When a woman's ability to function is affected, this is a sure sign that she needs treatment.

Postpartum psychosis, which is a much more severe and dangerous form of postpartum depression is extremely rare and only affects about 3 women in every 1000. Very rarely - in about 1 or 2 out of 1,000 previously-normal women - the depressive symptoms precede an acute psychosis. Most of the psychoses appear within two weeks of childbirth and disappear within two months, although they can continue longer. Signs of postpartum psychosis usually occur within the first few weeks postpartum. In some cases childbirth may result in low thyroid levels, which may also be a cause of depression.

As with premenstrual syndrome, very little is known about psychiatric illnesses that develop following childbirth and whether or not they differ from depressions and psychoses that occur at other times. In addition to the dramatic hormonal shifts that take place following childbirth, stressful life events, marital problems, fear of mothering, overly high expectations of motherhood, and lack of social supports may influence whether a woman progresses from the blues to a clinical depression.

Postpartum psychiatric illness was initially conceptualized as a group of disorders specifically linked to pregnancy and childbirth and thus was considered diagnostically distinct from other types of psychiatric illness. More recent evidence suggests that postpartum psychiatric illness is virtually indistinguishable from psychiatric disorders that occur at other times during a woman's life.