经前综合症（Premenstrual syndrome，PMS），有时被称为经前紧张症（PMT），是在女性月经来潮之前一至二周出现的生理及心理相关症状 。症状因人而异，约在月经出现时结束 。常见症状包括粉刺、乳房压痛、腹胀、容易疲倦、易怒及情绪上的改变 。症状一般会持续六天。多数育龄妇女（约80%）都有一些经前综合征的症状，而美国家庭医生学将把经前综合症限定为具有“严重妨碍某些方面的生活功能”症状。同一位女性其经前综合症的症状或是出现的时间也会随时间而改变。在怀孕时或是更年期不会有经前综合症的症状。

Premenstrual dysphoric disorder (PMDD) is a severe and disabling form of premenstrual syndrome affecting 3–8% of menstruating women. The disorder consists of a "cluster of affective, behavioral and somatic symptoms" that recur monthly during the luteal phase of the menstrual cycle. PMDD was added to the list of depressive disorders in the Diagnostic and Statistical Manual of Mental Disorders V in 2013. The exact pathogenesis of the disorder is still unclear and is an active research topic. Treatment of PMDD relies largely on antidepressants that modulate serotonin levels in the brain via serotonin reuptake inhibitors as well as ovulation suppression using contraception.