Aims. To investigate the relationship between antenatal and postpartum depression and anxiety and to explore associated maternal characteristics. Methods. From a population-based sample of 1,555 women attending two obstetric clinics in Sweden, all women with an antenatal psychiatric diagnosis (n=220) and a random selection of healthy women (n=500) were contacted for a second assessment three to six months postpartum. The Primary Care Evaluation of Mental Disorders was used for evaluation on both occasions. Results. Fewer cases of depressive and/or anxiety disorders were prevalent postpartum compared with the second trimester screening. Depression and/or anxiety were prevalent in 16.5% of postpartal women versus 29.2% of pregnant women. There was a significant shift from a majority of subthreshold diagnoses during pregnancy to full Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) diagnoses during the postpartum period. A history of previous psychiatric disorder, living single, and obesity were significantly associated with a new-onset postpartum psychiatric disorder. The absence of a previous psychiatric disorder was significantly associated with a postpartum recovery of depression or anxiety. Conclusions. Depression and anxiety appear to be less common postpartum than during pregnancy.