Formation of the Menstrual Cycle in Adolescent Girls and Hormonal Changes During Puberty

Abstract

Puberty is a complex biological transition during which the child’s body gradually acquires
reproductive, endocrine, somatic, and psychosocial maturity. In adolescent girls, one of the most
important markers of pubertal development is the onset and subsequent maturation of the menstrual
cycle. Menarche, or the first menstrual bleeding, usually occurs after the activation of the
hypothalamic–pituitary–gonadal axis and reflects the progressive interaction between the
hypothalamus, pituitary gland, ovaries, uterus, and peripheral endocrine tissues. However, the
establishment of regular ovulatory cycles does not occur immediately after menarche. During the
first postmenarchal years, menstrual cycles are often irregular because the neuroendocrine
mechanisms controlling gonadotropin-releasing hormone, luteinizing hormone, follicle-stimulating
hormone, estrogen, and progesterone secretion are still maturing. This article discusses the
physiological formation of the menstrual cycle in adolescent girls, the hormonal changes of puberty,
normal and abnormal menstrual patterns, and the clinical importance of monitoring menstruation as
an indicator of adolescent reproductive health