Age at Menarche among Indonesia Boarding School Students Nur Rochmah1, Muhammad Faizi1*, Yuni Hisbiyah1, Rayi Kurnia Perwitasari, Qorri ‘Aina, and Nur Lailatun Ni’mah Abstract Background: Menarche is a crucial indicator of a female’s sexual development because of the interaction of the hypothalamus-pituitary-ovarian axis with the reproductive and endocrine systems. The