美国每年合法终止妊娠者约有一百多万,中期妊娠流产则占10%。在孕13～16周终止妊娠,宫颈扩张和刮宫是主要步骤,而适度扩张富颈一直存在问题。机械扩张宫颈常发生组织损伤(宫颈裂伤、假通路形成、子宫穿孔)及潜在的远期影响(宫颈机能不全、早产及自然流产)。通过逐渐软化和扩张宫颈等方法使富颈成熟,以力争减少并发症的发生。 In the United States, there are about one million lawful termination of pregnancy each year, and 10% of miscarriage in the middle of pregnancy. In pregnancy 13 to 16 weeks to terminate the pregnancy, cervical dilatation and curettage is the main step, while moderate expansion neck has been a problem. Mechanical dilatation Cervical lesions often occur (cervical laceration, false passage formation, uterine perforation) and potential long-term effects (cervical insufficiency, premature birth and spontaneous abortion). By gradually softening and expansion of the cervix and other methods to make the neck mature, in an effort to reduce the incidence of complications.