General overview of depression can be found in the main article.
Epidemiology and Risk
- The incidence of MDD during pregnancy is 7.5%, while period prevalence is 12.7%.
- The strongest risk factor is a history of postpartum MDD with a previous pregnancy (25-50% recurrence rate)
- Depression during pregnancy is associated with increased risk of pre-term birth and low birth-weight (Meta-analysis, Grote 2010)
- Women treated with SSRI's have 2-3x greater risk for preterm birth and delivering low-birth-weight infants, compared to women not treated with SSRIs.
- Despite in-utero SSRI exposure, there was no effect in infant growth at 12-mo in a prospective observational study, i.e., premature and low-weight babies caught up.
- Baby blues refers to a brief period (<10days) of depressed mood and mild dysfunction without suicidality.
- prevalence if "baby blues" is 80% 
- postpartum depression is DSM-IV specifier for major depressive disorder, ("with postpartum onset") defined as onset within four weeks of delivery.
- feeling of guilt and worthlessness often dominate, while depressed mood is less common.
- up to 60% of women with postpartum MDD may have obsessive/intrusive thoughts about harming the infant.
- MD must rule out postpartum autoimmune thyroiditis (8% of postpartum women), which can mimic MDD
- Interpersonal therapy and cognitive behavior therapy are effective in treating MDD with postpartum onset.
- Light therapy has not been shown to be effective in patients with postpartum major depression.
- SSRIs are affective in moderate and severe depression; they are generally considered safe in breastfeeding.
 Groto NK, et.al. A meta-analysis of depression during pregnancy and the risk of preterm birth, low birth weight, and intrauterine growth restriction. Arch Gen Psychiatry. 2010 Oct;67(10):1012-24
 Wisner KL, et.al. Does Fetal Exposure to SSRIs or Maternal Depression Impact Infant Growth? Am J Psychiatry. 2013 May 1;170(5):485-93.
 Hirst KP., et.el. Postpartum Major Depression. Am Fam Physician. 2010 Oct 15;82(8):926-933