Premenstrual Dysphoric Disorder (PMDD) is a severe cyclical disorder affecting menstruating individuals characterised by distressing affective, cognitive, and physical symptoms that substantially impair daily functioning. Although formally recognised in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5; American Psychiatric Association, 2013), PMDD remains under-recognised, frequently misdiagnosed, and lacking consistent understanding among healthcare practitioners. While research on PMDD has expanded considerably in recent years, it continues to be shaped by ongoing debate and by the wider cultural and historical stigma surrounding menstruation and menstrual health. The historical neglect of menstrual health within medicine and psychiatry has reflected broader gendered and cultural biases. Dominant narratives often characterised menstruation as a source of instability or dysfunction, shaping both public attitudes and clinical approaches to menstrual disorders.

This thesis examines barriers to the timely identification, diagnosis, and treatment of PMDD, and the impact of living with PMDD with the current treatment options available. It focusses on both healthcare-practitioner knowledge and the lived experiences of racially and ethnically minoritised women and people who menstruate. Part A presents a scoping review of healthcare-practitioner mental-health literacy (MHL) relating to PMDD. The review synthesised evidence across four domains; knowledge, awareness, attitudes, and perceptions and revealed persistent deficits in understanding diagnostic criteria and evidence-based treatment, together with stigmatising beliefs and systemic constraints such as time pressure and inadequate training.

Part B presents a qualitative empirical study exploring the lived experiences of racially and ethnically minoritised women and people who menstruate in discovering, diagnosing, and managing PMDD. Thematic analysis identified themes of delayed recognition, treatment trials, and living with PMDD in the current time.

Taken together, the findings highlight the interplay between limited practitioner literacy, stigma, and sociocultural barriers that perpetuate inequities in PMDD care. They underscore the need for enhanced professional training, culturally responsive practice, and adaptation to racial, cultural, and religious differences, recognising the complex ways menstruation is shaped by culture, identity, and belief. Enhancing healthcare-practitioner education, integrating menstrual health within early health curricula, and developing culturally sensitive approaches to diagnosis and treatment are essential steps toward equitable and compassionate care for those affected by PMDD.