Using interpretive descriptive methodology, this qualitative research explores midwives' perceptions of mental health and the assessment of maternal mental health during pregnancy. Current literature suggests that maternal mental health problems are associated with an increased risk of morbidity and mortality, and occur more frequently during pregnancy than in the postnatal period.

Purposive and theoretical sampling strategies were used to recruit participants, and five focus groups were carried out, consisting of a total of twenty-five midwives working as lead maternity carers (LMCs), who provide continuity of care to a caseload of women throughout pregnancy, labour and birth, and the postnatal period. The data was analysed using qualitative content analysis. One overarching theme that emerged was 'The disparity between needs and service provision', illuminating the significance of the absence of appropriate services to meet the needs of women with mild or moderate maternal mental health problems such as anxiety and mild/moderate depression.

As a result of this disparity, the midwives carried the weight of maternal mental health problems that did not meet the criteria for referral to the Maternal Mental Health (MMH) service. 'Carrying the weight' is integral to all three sub-themes, which are: 'Not meeting needs', 'The anxious woman needing extra support', and 'Safeguarding women's wellbeing and welfare'. The overarching statement of the research is: 'Holding the problem: plugging the gap between women and the service'. Results revealed that the participant midwives plugged the gap between women and the service in order to safeguard the women?s wellbeing and welfare when appropriate services were not available to meet their needs. This caused some difficulties for the midwives and evidently influenced their antenatal maternal mental health assessment and screening practices.