[Diagnosis and management of amenorrhea in adolescent girls]

Amenorrhea in adolescents can be primary, with or without breast development, or secondary. Whether amenorrhea is primary or secondary, height, body mass index, food intake, the level of physical activity per week, the presence of hirsutism or galactorrhea, pelvic pain and past history of intercourse need to be investigated. Initially, blood tests should include hCG, FSH, estradiol, testosterone and prolactin serum levels. This screening will discriminate between hypogonadotropic hypogonadism and amenorrhea from primary ovarian insufficiency (POI). In case of primary amenorrhea, hypogonadism may be due to congenital hypogonadotropic hypogonadism (HH) or more rarely acquired HH. If FSH is elevated, amenorrhea is due to primary ovarian failure, mainly related to Turner syndrome. If pubertal development is normal, a pelvic ultrasound should be performed. It may visualize a hindering of menses output or less frequently an absence of uterus, as in Rokitansky syndrome or androgen insentivity syndrome. The most frequent etiologies of secondary amenorrhea are polycystic ovarian syndrome (PCOS), functional hypothalamic amenorrhea and less frequently POI and hyperprolactinemia. The differential diagnoses of PCOS are late-onset 21-hydroxylase deficiency and very rare ovarian or adrenal tumors. When contraception is not necessary, hormonal replacement therapy, including estrogen and progestins should be administered in order to avoid hypoestrogenism. In case of PCOS, sequential progestins can be prescribed. A contraceptive pill can be considered when contraception is needed and/or when hyperandrogenism needs to be treated.