Menstrual hygiene management remains a major challenge in developing countries and is sometimes unaddressed in public places such as schools. Although menstruation is an important part of adolescent girls’ lives, if not managed in a dignified and healthy manner, it can result in adverse health effects. Understanding determinants affecting menstrual hygiene management in schools is essential in ensuring that the sanitation conditions do not present difficulty choices for menstruating girls. The objectives of the study were to assess the cultural factors, to examine available WASH facilities and to establish menstrual waste disposal methods and practices that affect menstrual hygiene management among adolescent girls. The study targeted 383 adolescent school girls from Chuka Sub-County. Data was collected using structured questionnaires and analysed using descriptive and inferential statistics. The study was based on voluntary participation. Inadequate knowledge on menstrual hygiene management prior to menstrual onset, behaviour restrictions and the perception of uncleanliness when menstruating affected menstrual hygiene management among the adolescent girls in schools. From this study findings, negative attitude towards menstrual materials (r=0.144, p-value=0.001) and lack of sanitary materials (r=0.752, p-value=0.000) constrained menstrual hygiene management. Findings showed that 49.9% of the adolescent girls accessed limited menstrual disposal facilities and 39.7% reported lack of hand washing facilities in schools. Presence of hygiene facilities in schools had a significant relationship with changing of sanitary towels (r=0.610, p-value=0.000), bathing (r=0.781, p-value=0.008) and washing of hands after menstruation (r=0.419, p-value=0.000). In addition, inadequate menstrual hygiene management facilities such as water, sanitary bins, sanitary towels, private toilets and changing rooms affected menstrual hygiene management in schools. Limited resources for purchasing menstrual hygiene management materials, the shame of being associated with menstruation, the perception of uncleanliness during menstruation and fear of being mocked by boys on staining of cloths and shared toilets constrained menstrual hygiene management in schools. Existence of interaction restrictions with boys during menstruation was a factor which qualified as a menstruation taboo and created a sense of stigma for the menstruating adolescent girls. Failure to make girls aware of menstrual hygiene prior to onset of menstruation reduced their probability of maintaining hygiene on their menarche (r=0.371, p-value=0.000). Availability of soap and water was likely to increase changing of menstrual materials while in school (r=0.313, p-value=0.001) and bathing during menstruation (r=0.507, p-value=0.008). Girls’ comfortability with disposal places for menstrual materials affected changing of menstrual materials in schools (r=0.882, p-value=0.000). The study concluded that WASH facilities were not sufficient to meet the needs of menstruating adolescent girls which amplified sanitation and hygiene stresses in schools. It was also concluded that experiences of humiliation in schools during menstruation continue to be invisible which represented the menstruation stigma that girls so silently encountered in schools. A holistic menstrual hygiene response in schools that entails provision of girls friendly WASH facilities, menstrual supplies and appropriate information is needed. The study recommended government support and advocacy on provision of dignified menstrual hygiene management options in schools. As well, there is need for eradicating the stigma associated with menstruation through campaigning against restrictive social cultural values which seem so embedded in the society