Menstrual Hygiene Day Menstrual Hygiene Day Menstrual Hygiene Day (MHD, MH Day in short) is an annual awareness day on May 28 to highlight the importance of good menstrual hygiene management (MHM). It was initiated by the German-based NGO WASH United in 2014 and aims to benefit women and girls worldwide. The 28th was selected to acknowledge that 28 days is the average length of the menstrual cycle. In low-income countries, girls’ choices of menstrual hygiene materials are often limited by the costs, availability and social norms. Adequate sanitation facilities and access to feminine hygiene products are one part of the solution. Creating
Menstrual synchrony more women become closer together in time than they were several months earlier.. After the initial studies, several papers were published reporting methodological flaws in studies reporting menstrual synchrony including McClintock's study. In addition, other studies were published that failed to find synchrony. The proposed mechanisms have also received scientific criticism. A 2013 review concluded that menstrual synchrony likely does not exist. Martha McClintock published the first study on menstrual synchrony among women living together in dormitories at Wellesley College, a women's liberal arts college. McClintock hypothesized that pheromones could cause menstrual cycle synchronization. However, other mechanisms have been proposed,