Objective: The objective of this study was to evaluate attachment and its association to obstetric and demographic factors as well as emotional well-being using a standard measure of prenatal attachment during pregnancy. Background: The strength of the mothers relationship with her baby has important implications in the postnatal period, influencing the relationship she develops with her child, and the quality of the care she provides. Methods: This was a population-based longitudinal survey comprising a consecutive sample from a one-year cohort in a Swedish county. In this study the three subscales of PAI-R (Prenatal Attachment Inventory - Revised) were used for evaluation of attachment. In total, 718 pregnant women participated in this study. Results: Women with elevated levels of depression (HADS-D greater than8) recorded lower attachment scores across all three PAI-R subscales. Lack of perceived support from partner was associated with lower scores on Interaction. Lack of support from own mother and own father were also associated with lower scores on all subscales. Attachment was also associated with feelings about the approaching birth and about the first weeks with the newborn, with women who reported less than positive feelings recording lower scores on each of the PAI-R subscales. Conclusion: A focus on attachment during antenatal care and the use of PAI-R during pregnancy provides a means of identifying those women who show lower levels of attachment and possible emotional problems that may impact on emotional health and the birth process.