We evaluated whether the emotional reactions of women at 2-6 weeks after the prenatal diagnosis of a lethal anomaly and at 3 months after perinatal loss might be predicted by previous stress and acute psychological defence reactions to the diagnosis. Previous stress was defined objectively as a history of major life event(s) and having received professional mental health treatment in the past, and subjectively as the disposition for feelings of inadequacy and anxiety. Forty-one women were interviewed and completed measures on their history of major life events, whether they had received professional mental health treatment in the past, inadequacy, acute psychological defence reactions and perinatal grief. Regression analyses showed that inadequacy was the most strongly positive predictor of perinatal grief shortly after receiving the unfavourable diagnosis and three months after perinatal loss. In addition to inadequacy, having received professional mental health treatment in the past led to significantly more intense grief, but only shortly after receiving the unfavourable diagnosis. Previous life events intensified grief three months after perinatal death. The grieving process was significantly moderated by the defence of 'principalization' while it was significantly intensified by 'turning aggression against oneself', but only shortly after receiving the unfavourable diagnosis. These effects were not contaminated by relationships with pregnancy-related variables. Our findings imply that psychological support for women with perinatal loss should particularly be offered to those who have been identified as generally anxious, who have reported previous major life events and have received professional mental health treatment in the past.