Better known as amenorrhea, amenia is the absence or cessation ofAmenia: Better known as amenorrhea, amenia is the absence or cessation of menstruation. Amenorrhea is conventionally divided into primary andsecondary amenorrhea. With primary amenorrhea, menstruation never takesplace. It fails to occur at puberty. With secondary amenorrhea,menstruation starts but then stops. The absence of menstruation during pregnancy is a form of physiologic amenorrhea, physiologic in the sense thatit is completely normal and is not caused by anything pathologic. Amenorrheaduring lactation is another type of physiologic amenorrhea. The word"amenorrhea" is compounded from three Greek roots "a-", no + "men", month +"rhoia", flow = no monthly flow.