Purpose <p>Perinatal depression and anxiety are prevalent complications affecting 18–26% of pregnancies worldwide. This study investigated the influence of personality traits and partner attachment styles on depressive and anxiety symptoms in Slovenian women. We compared the results longitudinally at two time points: during pregnancy and at 6 weeks postpartum.</p> Methods <p>A non-clinical sample of 325 women in their third trimester and a clinical sample of 49 women diagnosed with perinatal depression and/or anxiety were assessed during pregnancy and 6 weeks postpartum. We investigated how the personality traits of women and their partner attachment styles influence their clinical symptoms and how they change after giving birth. Clinical symptoms were measured by Edinburgh Postnatal Depression Scale (EPDS) and Zung Anxiety Scale, partner attachment by Experiences in Close Relationships-Revised (ECR-R) and personality traits by Big Five Inventory (BFI).</p> Results <p>Higher neuroticism, lower openness and lower extraversion were those personality traits, which were associated with higher levels of depressive and anxiety symptoms in pregnant women in both clinical and non-clinical samples. Higher partner anxiety attachment scores were also associated with depressive and anxiety symptoms in women in both samples. The clinical group receiving outpatient psychiatric support showed significant improvements in depressive and anxiety symptoms after birth when compared with non-clinical group of women.</p> Conclusions <p>This study emphasizes the importance of personality traits and partner attachment style as predictors of perinatal depressive and anxiety symptoms. Prenatal screening and interventions addressing these risk factors may prevent or reduce the severity of perinatal depressive and anxiety disorders. Further research is needed to assess the efficacy of such interventions in high-risk populations.</p> Trial registration <p>Not applicable.</p>