In this article, we will review the etiology and management of amenorrhea in adolescent and young adult women, beginning with the diagnostic work-up and followed by etiologies organized by system. Most cases of amenorrhea are caused by dysfunction of the hypothalamic-pituitary-ovarian (HPO) axis, which is the major regulator of the female reproductive hormones: estrogen and progesterone. We begin by reviewing hypothalamic etiologies, including eating disorders and relative energy deficiency in sport. Then, pituitary causes of amenorrhea are reviewed, including hyperprolactinemia, empty sella syndrome, Sheehan's syndrome and Cushing's syndrome. Next, ovarian causes of amenorrhea are reviewed, including polycystic ovarian syndrome and primary ovarian insufficiency. Finally, other etiologies of amenorrhea are discussed, including thyroid disease, adrenal disease and reproductive tract anomalies. In conclusion, there is a wide and diverse range of causes of amenorrhea in adolescents that originate from any level of the HPO axis, as well as anatomic and chromosomal etiologies. Treatment should be focused on the underlying cause. Preservation of bone density and risk of fractures should be discussed with amenorrheic patients since many causes of amenorrhea can result in decreased bone density and may be irreversible.

在本文中，我们将回顾青春期和年轻成年女性闭经的病因和治疗，从诊断检查开始，然后按系统组织病因。大多数闭经病例是由下丘脑-垂体-卵巢 (HPO) 轴功能障碍引起的，HPO 轴是女性生殖激素：雌激素和孕激素的主要调节剂。我们首先回顾下丘脑病因，包括运动中的饮食失调和相对能量缺乏。然后，回顾了导致闭经的垂体原因，包括高催乳素血症、空蝶鞍综合征、希恩综合征和库欣综合征。接下来，回顾了导致闭经的卵巢原因，包括多囊卵巢综合征和原发性卵巢功能不全。最后，讨论了闭经的其他病因，包括甲状腺疾病、肾上腺疾病和生殖道异常。总之，青少年闭经的原因多种多样，其起源于 HPO 轴的任何水平，以及解剖和染色体病因。治疗应侧重于根本原因。应与闭经患者讨论保持骨密度和骨折风险，因为闭经的许多原因可导致骨密度降低并且可能是不可逆的。