As much as 40 percent of girls choose not to go to school for an average of three days each month when they have their period because there are no appropriate restroom facilities, according to a study by the International Center for Diarrhoeal Disease Research, Bangladesh (ICDDR,B). The National Hygiene Baseline Survey says that menstrual hygiene is a serious challenge for girls in Bangladesh due to a lack of understanding and general education about it.