"a recent systematic literature review suggests that single mothers are at an increased risk for postpartum depression (ppd) compared to partnered mothers. however, the roles of potential contributing factors, such as socio-economic status, education or social support, are not well understood. in particular, there is a lack qualitative research to assist in exploring this phenomenon from the perspective of single mothers themselves. the purpose of this qualitative study was to examine single mothers' perceptions of risk for ppd in order to begin to elucidate the psychosocial mechanisms for the relationship between single status and risk for ppd. using a grounded theory approach, 11 single mothers within 1-year postpartum underwent a one-time, open-ended research interview pertaining to their experiences as single mothers during the postpartum period. analysis of the data identified social support as the key factor perceived to determine risk for ppd. specifically, participants considered single mothers as a group to be at greater risk for ppd compared to partnered mothers, because of a perceived disparity in level of available social support. these findings suggest that clinical or public health interventions designed to improve or expand upon the support networks available to single mothers may show promise in the prevention and treatment of ppd."--abstract