The data suggested around 1.6% did – equivalent to around 31 million women and girls globally. Symptoms of PMDD include mood changes (such as depression and anxiety), physical symptoms (such as breast tenderness, and joint pain), and cognitive problems (difficulty concentrating or memory complaints). 'Because diagnostic criteria is so strict, this is likely an underestimation of the lifetime prevalence of PMDD, and many more women and girls may be undiagnosed. 'There is little training around PMDD for psychiatrists or indeed medical students. The paper ‘The prevalence of premenstrual dysphoric disorder: Systematic review and meta-analysis’ is published in the Journal of Affective Disorders.