Postpartum depression (PPD) has detrimental consequences to the women, their infants and families. The aim of the present study was to assess the association between adult abuse and PPD.This study was based on data from 53,065 pregnant women in the Norwegian Mother and Child Cohort Study (MoBa), conducted by the Norwegian Institute of Public Health. Women were recruited through a postal invitation in relation to a routine ultra-sound invitation at week 18 of gestation. Exposure to adult emotional, sexual, physical abuse was based on self-report at week 30, also differentiating if the perpetrator was known or a stranger, and whether the abuse was recent or not (<12 month since abuse). PPD was measured with a four items version of the Edinburgh Postnatal Depression Scale (EDS) at six months postpartum. The associations between different types of adult abuse and PPD were performed with logistic regression, adjusting for age, parity, civil status, education, child abuse, social support, and depression prior to pregnancy.Altogether, 11% had PPD, and 19% had been exposed to adult abuse. Women reporting adult abuse had an 80% increased fully adjusted odds of PPD (OR 1.8 95% CI 1.7-1.9) compared to non-abused women. There was a tendency towards higher odds of PPD for women reporting combinations of adult abuse (emotional, sexual and physical), as compared with those reporting sexual, emotional or physical abuse only. Exposure from known perpetrator was more strongly associated with PPD than exposure from an unknown perpetrator. Compared with women without adult abuse, the fully adjusted odds of PPD was 2.6 (95% CI 2.4-2.9) higher for women with any recent adult abuse and 1.5 (95% CI 1.5-1.7) higher for women with any adult abuse, but not recent.The results from this large prospective population-based cohort study support initiatives aiming to assess and adequately address abuse when counseling and treating women of PPD.