精子質量(liang)下(xia)降：精子質量(liang)下(xia)降是指(zhi)精子的數(shu)量(liang)、成(cheng)活率及活動能力、密度(du)等在同等體積(ji)的水平(ping)下(xia)降低。

稀：稀(xi)指(zhi)(zhi)稀(xi)薄如(ru)水，呈(cheng)乳白色液體，是(shi)少精(jing)(jing)(jing)癥(zheng)(zheng)(zheng)的(de)一種。一般將少精(jing)(jing)(jing)癥(zheng)(zheng)(zheng)分為特發(fa)性(xing)(xing)少精(jing)(jing)(jing)癥(zheng)(zheng)(zheng)、原發(fa)性(xing)(xing)少精(jing)(jing)(jing)癥(zheng)(zheng)(zheng)和繼發(fa)性(xing)(xing)少精(jing)(jing)(jing)癥(zheng)(zheng)(zheng)。特發(fa)性(xing)(xing)少精(jing)(jing)(jing)癥(zheng)(zheng)(zheng)占不育癥(zheng)(zheng)(zheng)人群的(de)11%-15%。少精(jing)(jing)(jing)子(zi)(zi)(zi)(zi)癥(zheng)(zheng)(zheng)是(shi)指(zhi)(zhi)中(zhong)(zhong)的(de)精(jing)(jing)(jing)子(zi)(zi)(zi)(zi)數目低(di)于(yu)正常(chang)具有生(sheng)(sheng)育能力男性(xing)(xing)的(de)一種病癥(zheng)(zheng)(zheng)，國際衛生(sheng)(sheng)組織規定男性(xing)(xing)的(de)精(jing)(jing)(jing)子(zi)(zi)(zi)(zi)在每毫升不低(di)于(yu)2千(qian)(qian)萬(wan)(wan)，如(ru)果(guo)低(di)于(yu)2千(qian)(qian)萬(wan)(wan)就(jiu)(jiu)歸為少精(jing)(jing)(jing)子(zi)(zi)(zi)(zi)癥(zheng)(zheng)(zheng)，生(sheng)(sheng)育方面就(jiu)(jiu)會有很大影響。如(ru)果(guo)再(zai)細分的(de)話(hua)，就(jiu)(jiu)是(shi)小(xiao)于(yu)2千(qian)(qian)萬(wan)(wan)，大于(yu)1千(qian)(qian)萬(wan)(wan)之(zhi)間，稱(cheng)為輕(qing)度(du)(du)少精(jing)(jing)(jing)子(zi)(zi)(zi)(zi)癥(zheng)(zheng)(zheng)，如(ru)果(guo)小(xiao)于(yu)1千(qian)(qian)萬(wan)(wan)，大于(yu)500萬(wan)(wan)，稱(cheng)為中(zhong)(zhong)度(du)(du)，如(ru)果(guo)小(xiao)于(yu)500萬(wan)(wan)就(jiu)(jiu)稱(cheng)為重度(du)(du)少精(jing)(jing)(jing)子(zi)(zi)(zi)(zi)癥(zheng)(zheng)(zheng)，如(ru)果(guo)說在高倍(bei)視野下只(zhi)能發(fa)現(xian)幾個精(jing)(jing)(jing)子(zi)(zi)(zi)(zi)，或(huo)者離心(xin)后才能看見幾個精(jing)(jing)(jing)子(zi)(zi)(zi)(zi)就(jiu)(jiu)非常(chang)少了，稱(cheng)為嚴重的(de)少精(jing)(jing)(jing)子(zi)(zi)(zi)(zi)癥(zheng)(zheng)(zheng)。

凡(fan)量(liang)(liang)少于1.5ml者均可診斷為本病。量(liang)(liang)少者臨床上多伴有腰(yao)膝酸軟，神疲乏力，形體瘦弱，或(huo)少腹脹(zhang)痛，或(huo)射精時刺痛。1、3～5天內未房事(shi)事(shi)而(er)一次射精量(liang)(liang)少于2m1，或(huo)少有數(shu)滴。2、檢查(cha)連(lian)續(xu)3次以(yi)上，精子計數(shu)每ml均在0.2億(yi)以(yi)下。3、排除近期過頻(pin)，遺精、滑精過頻(pin)等，或(huo)素有射精不全(quan)病史，或(huo)久病剛愈而(er)者。