Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of Alabama, Birmingham, Birmingham, AL 35233, USA.
Obstet Gynecol Clin North Am. 2012 Mar;39(1):25-33. doi: 10.1016/j.ogc.2011.12.001. Epub 2012 Jan 4.
Contemporary evidence supports the concept that cervical insufficiency is anything but a well-defined and distinct clinical entity. Instead, it is only 1 component of the larger and more complex preterm birth syndrome. Premature cervical ripening, as evidenced by shortening and effacement beginning at the internal os, provides strong evidence that parturition has begun and is the result of multiple interrelated pathways and inciting factors. Ultrasonographic screening of the cervix and treatment with cerclage for cervical shortening in the mid-trimester is reserved for women with prior spontaneous preterm birth (Fig. 1). Although cerclage benefit increases as the cervix shortens to less than 25 mm, it is appropriate to offer cerclage to women with shortened cervical length of less than 25 mm, and particularly those with a coexistent U-shaped funnel.
目前的证据支持这样一种观点，即宫颈机能不全绝不是一种明确和独特的临床实体。相反，它只是更广泛和更复杂的早产综合征的一个组成部分。正如宫颈内口缩短和消失所证明的那样，宫颈过早成熟强烈表明分娩已经开始，这是多种相互关联的途径和诱发因素的结果。对于有既往自发性早产史的妇女，采用超声筛查宫颈和宫颈环扎术治疗宫颈缩短（图 1）。尽管随着宫颈缩短至 25 毫米以下，环扎术的获益增加，但对于宫颈长度缩短至 25 毫米以下的妇女，特别是那些同时存在 U 形漏斗的妇女，提供环扎术是合适的。
