Doulas are assistants who support mothers during pregnancy, labour, birth, and postpartum. Gestational DI occurs only during pregnancy and the postpartum period. There is some evidence that postpartum doula support can increase breastfeeding and decrease postpartum depression. This probably results from a physiological hypercoagulability in pregnancy that protects against postpartum hemorrhage. Uterine inversion is often associated with significant postpartum bleeding. Preventive group therapy has proven effective as a prophylactic treatment for postpartum depression. She was diagnosed with postpartum psychosis. A 2011 review found it unclear whether breastfeeding affects the risk of postpartum depression. Estradiol has been studied in the treatment of postpartum depression and postpartum psychosis. Specific complications include obstructed labour, postpartum bleeding, eclampsia, and postpartum infection. This became known as puerperal or postpartum psychosis. Severe complications appear to be more common in postpartum mothers. During the subacute postpartum period, psychological disorders may emerge. Eligibility was limited to children up to age 4 and excluded non-breastfeeding postpartum women. Self determined that she suffered from postpartum psychosis.