Opiate addiction has been widely documented to have negative impact on pregnancy course and outcome. Unfavorable psychosocial situation of addicted women predispose for poor processing of the physiological and psychological demands of pregnancy. Thus aim of our study was to investigate the psychological mood state of opiate addicts during pregnancy and postpartum in comparison to healthy women. In a case-controlled, prospective, longitudinal study nine pregnant opiate addicts and nine healthy pregnant women matched by age, level of education and gestational age at birth were interviewed in the third trimester of pregnancy and postpartum. Standardized questionnaires and inventories for assessment of the general psychopathology and emotional state, the perceived self-efficacy expectancy, the psychosocial adaptation to pregnancy and the fear of delivery, respectively were applied. Addicted women achieved significantly higher scores in the test assessing general psychopathology and emotional state before delivery compared to abstinent women. Interestingly this difference was unverifiable postpartum. This study reaffirms the presumption of a disadvantageous psychological condition in pregnant opiate addicts in comparison to healthy pregnant women for the first time in a prospective case-control study design.