房事前将外用药物放入阴道内,杀死精子或使其失去活动能力:或利用药物的机械作用,阻碍精子活动,以削弱精子的能量,或在子宫颈口形成隔膜(如油脂或泡沫剂),以阻止精子进入子宫,可达到避孕目的。多年来常用的药物为有机汞(如醋酸苯汞)及弱酸,虽有杀精子作用,但有效率低,且可抑制阴道内正常杆菌。近年来国内外研制成功新型高效杀精子 The room before the topical drugs into the vagina, kill sperm or make them lose their ability to act: or use the mechanical effects of drugs, impede sperm motility, to weaken the energy of sperm, or in the cervix to form a diaphragm (such as grease or foam ), To prevent sperm into the uterus, can achieve the purpose of contraception. Over the years the commonly used drugs for organic mercury (such as phenylmercuric acetate) and weak acid, although the role of spermicidal, but the low efficiency, and can inhibit normal vaginal bacteria. In recent years, successful domestic and foreign research and development of new and efficient sperm