Amenorrhea is the external manifestation of female pathophysiological changes caused by many diseases, and it is a clinical symptom rather than a disease. According to the pathological changes and dysfunction of reproductive axis, it can be divided into hypothalamic amenorrhea, pituitary amenorrhea, ovarian amenorrhea, uterine amenorrhea and hypoplastic amenorrhea of lower reproductive tract.
Amenorrhea can also be divided into primary and secondary, physiological and pathological. Primary amenorrhea refers to age >; 14 years old, with undeveloped secondary sexual characteristics; Or age >; 16 years old, secondary sexual characteristics have developed and menstruation is still coming. Does secondary amenorrhea mean stopping menstruation for more than 6 months after the establishment of normal menstrual cycle, or for more than 3 cycles according to the original menstrual cycle? Physiological amenorrhea refers to amenorrhea during pregnancy, lactation and menopause. Pathological amenorrhea is caused directly or indirectly by functional or organic diseases of central nervous system-hypothalamus-pituitary-ovary axis and target organ uterus.