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

Puberty is a complex biological transition during which the child’s body gradually acquiresreproductive, endocrine, somatic, and psychosocial maturity. In adolescent girls, one of the mostimportant markers of pubertal development is the onset and subsequent maturation of the menstrualcycle. Menarche, or the first menstrual bleeding, usually occurs after the activation of thehypothalamic–pituitary–gonadal axis and reflects the progressive interaction between thehypothalamus, pituitary gland, ovaries, uterus, and peripheral endocrine tissues. However, theestablishment of regular ovulatory cycles does not occur immediately after menarche. During thefirst postmenarchal years, menstrual cycles are often irregular because the neuroendocrinemechanisms controlling gonadotropin-releasing hormone, luteinizing hormone, follicle-stimulatinghormone, estrogen, and progesterone secretion are still maturing. This article discusses thephysiological 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 asan indicator of adolescent reproductive health