WASH Disparities Impact MHM: The study underscores the critical link between disparities in WASH facilities and MHM practices among school girls. Addressing these inequalities is essential to promote healthy menstrual hygiene practices and overall well-being among students.

Educational and Economic Factors Play a Role: The trend of disparities between public and private schools is influenced by parents' educational status and income levels. This highlights the need for targeted interventions to bridge the gap in WASH facilities and promote equitable access to resources for all students.

Policy Implications for Sustainable Development Goals: Inadequate WASH facilities not only affect MHM but also hinder Nigeria's progress towards achieving Sustainable Development Goals related to health, education, gender equality, and sanitation. Investing in school WASH infrastructure is crucial for advancing these development objectives and ensuring a healthy learning environment for all students.