Menstrually-related mood disorders and postpartum depression: Convergent aspects in aetiology

Females diagnosed with Menstrually-related mood disorders (MRMDs) have more risk to develop postpartum depression (PPD). There are overlapping symptoms between MRMDs and PPD such as anxiety, depressed mood, irritability, that can contribute to a lower quality of life. MRMDs and PPD share components in their etiology such as dramatic hormonal oscillations, and alterations in Hypothalamus-Pituitary-Adrenal (HPA) axis activity that may impair GABAergic neurotransmission. As well, stressful events that impact HPA regulation may play an important role in the etiology of MRMDs and PPD. Here we review common hormone fluctuations across the menstrual cycle and pregnancy/postpartum to identify shared pathways that could contribute to greater sensitivity in people with MRMDs and PPD. This review summarizes hormone sensitivity, HPA axis activity and neurosteroids effects on GABAergic transmission and the potential role of chronic stress in developing MRMDs and PPD. In addition, other potential etiopathological factors, such as serotonin and the immune system, are discussed. Investigating the etiopathology of MRMDs and PDD will help to better understand the complexity of factors involved in these disorders that affect females across the reproductive years.