Postpartum period
During the subacute postpartum period, psychological disorders may emerge. Among these are postpartum depression, posttraumatic stress disorder, and in rare cases, puerperal psychosis. Postpartum mental illness can affect both mothers and fathers, and is not uncommon. Early detection and adequate treatment is required. Approximately 25% – 85% of postpartum women will experience the "blues" for a few days. Between 7% and 17% may experience clinical depression, with a higher risk among those women with a history of clinical depression. Prevalence of PTSD following normal childbirth (excluding stillbirth or major complications) is estimated to be between 2.8 and 5.6% at 6 weeks postpartum.
Intrusive thought
Unwanted thoughts by mothers about harming infants are common in postpartum depression. A 1999 study of 65 women with postpartum major depression by Katherine Wisner "et al." found the most frequent aggressive thought for women with postpartum depression was causing harm to their newborn infants. A study of 85 new parents found that 89% experienced intrusive images, for example, of the baby suffocating, having an accident, being harmed, or being kidnapped.