經(jīng)量明顯減少,甚或點(diǎn)滴即凈,或經(jīng)期縮短不足兩天,經(jīng)量也少者,稱為月經(jīng)過少,又稱經(jīng)水澀少。一般認(rèn)為經(jīng)量少于30毫升,相當(dāng)于西醫(yī)月經(jīng)不調(diào)中的月經(jīng)稀少。月經(jīng)周期正常,經(jīng)量很少,甚或點(diǎn)滴即凈;也有經(jīng)期縮短不足兩天,經(jīng)量亦少,為本病的診斷要點(diǎn)。本病常為閉經(jīng)的前驅(qū)表現(xiàn)。月經(jīng)過少可與月經(jīng)周期異常并見,如月經(jīng)先期量少或月經(jīng)后期量少。如屬口服避孕藥或肌注避孕針而導(dǎo)致月經(jīng)過少,則應(yīng)停藥,并可參照本病論治。月經(jīng)過少的診斷,一般是指連續(xù)發(fā)生二次以上。如一貫月經(jīng)正常,突然月經(jīng)過少者,應(yīng)注意是否受孕早期的先兆流產(chǎn),或異位妊娠所表現(xiàn)的少量陰道出血,必須進(jìn)一步做有關(guān)檢查以鑒別。