Postpartum depression, or PPD, is depression that occurs in after they give birth. It can last a few weeks or several months, symptoms are similar to major depression that is not related a loss of interest or pleasure in life, fatigue, loss of feelings of worthlessness, unexplained weight loss or gain, insomnia, and thoughts about harming yourself, among others. Women PPD may also have thoughts about harming their baby.

PPD is not the more common and familiar “baby blues” also occur after a woman gives birth. This condition affects 80 percent of new mothers, features rapid mood shifts and includes symptoms such as irritability, crying, problems concentrating, and insomnia. It resolves shortly after childbirth, anywhere from within a few hours to within several days. In contrast, women with PPD have significant symptoms that occur within the first four weeks after childbirth.

PMS and PPD are intimately connected: PMS is a risk factor for PDD, and PPD is a risk factor for PMS. While experts know some the mechanisms behind PMS, the same can't be said for PPD. Experts do know that a woman's hormones exhibit extreme fluctuations right after childbirth, but studies show that those fluctuations don't appear to cause PPD. In addition, according to researchers, new fathers, who don't experience hormonal fluctuations, can also suffer from PPD. A 2005 study published in the British journal the Lancet analyzed data from the Avon Longitudinal Study of Parents and Children and found that 4 percent of fathers (compared to 10 percent of moth-ers) reported feelings of anxiety, hopelessness, and irritability within eight weeks of their child's birth.

Social factors, on the other hand, appear to play a role. Stress, poor marital relationships, previous depression, and a lack of support systems, all risk factors for PMS, are also correlated with whether a woman gets PPD. Other factors may include the dramatic lifestyle changes after having children, being a single mother, having an unwanted or unplanned pregnancy, and having an infant with temperament problems, such as colic.

Women who have PPD with one pregnancy are also more likely to experience it in subsequent pregnancies.

Postpartum Psychosis

Postpartum psychosis is an extreme form of PPD in which woman experiences a complete break with reality. PPP is rare: only 1 in 500 to 1 in 1,000 women experience it in the first delivery. (The risk dramatically rises to one in three for women who've had it previous pregnancies.) Many women with PPP aren't even aware that they have the condition. The most famous example of a woman with PPD in recent years is Andrea Yates, a Texas mother who drowned her five children. This mental illness is treated with antipsychotic medications.