2009年ACOG引产指南
2009年ACOG引产指南
CLINICAL MANAGEMENT GUIDELINES FOR OBSTETRICIAN–GYNECOLOGISTS
NUMBER 107, AUGUST 2009
Induction of Labor
引产术
More than 22% of all gravid women undergo induction of labor in the United States, and the overall rate of induction of labor in the United States has more than doubled since 1990 to 225 per 1,000 live births in 2006 (1). The goal of induction of labor is to achieve vaginal delivery by stimulating uterine contractions before the spontaneous onset of labor. Generally, induction of labor has merit as a therapeutic option when the benefits of expeditious delivery outweigh the risks of continuing the pregnancy. The benefits of labor induction must be weighed against the potential maternal and fetal risks associated with this procedure (2). The purpose of this document is to review current methods for cervical ripening and induction of labor and to summarize the effectiveness of these approaches based on appropriately conducted outcomes-based research. These practice guidelines classify the indications for and contraindications to induction of labor, describe the various agents used for cervical ripening, cite methods used to induce labor, and outline the requirements for the safe clinical use of the various methods of inducing labor.
在美国，大于22%的妊娠妇女要经历引产术，而且，美国截止2006年每1000例活产中已有225例引产，总引产率相比1990年翻了一倍还多。引产术是为了通过在自主宫缩之前刺激子宫收缩达到阴道分娩的目的。总的来说，引产术是当快速结束分娩的益处大于继续妊娠的风险时，作为一种治疗选择是有其优势的。引产的益处必须大过相关的母体和胎儿的潜在风险。该文献的目的是对当前宫颈成熟的方法、引产术做一综述，并在以效果为基础的研究的适当引导下，总结了这些方法的疗效。该实用指南对引产的适应证及禁忌证进行分类，描述了用于宫颈成熟的各种药物，引用了引产术的方法，并概括了临床各种安全引产术方法的要求。
Background
背景
In 1948, Theobald and associates described their use of the posterior pituitary extract, oxytocin, by intravenous drip for labor induction (3). Five years later, oxytocin was the first polypeptide hormone synthesized by du Vigneaud and associates (4). This synthetic polypeptide hormone has since been used to stimulate uterine contractions. Other methods used for induction of labor include membrane stripping, amniotomy, nipple stimulation, and administration of prostaglandin E analog
ues.
1948年，Theobald及其助手描述了他们将垂体后叶提取物，催产素，作为引产药静滴使用。五年后，催产素成为由du Vigneaud及其助手合成的第一种多肽激素。该合成多肽激素由此被用来刺激子宫收缩。其他引产术包括剥膜术、羊膜穿刺术、乳头刺激，和前列腺素E类似物的使用。
2009年ACOG引产指南
Cervical Ripening
宫颈成熟
The goal of cervical ripening is to facilitate the process of cervical softening, thinning, and dilating with resultant reduction in the rate of failed induction and induction to delivery time. Cervical remodeling is a critical component of normal parturition. Observed changes not only include collagen breakdown and rearrangement but also changes in the glycosaminoglycans, increased production of cytokines, and white blood cell infiltration (5). If induction is indicated and the status of the cervix is unfavorable, agents for cervical ripening may be used. The status of the cervix can be determined by the Bishop pelvic scoring system (Table 1) (6). An unfavorable cervix generally has been defined as a Bishop score of 6 or less in most randomized trials. If the total score is more than 8, the probability of vaginal delivery after labor induction is similar to that after spontaneous labor.
宫颈成熟的目的是指在引产失败和分娩前的引产时，让宫颈软化、变薄，并随之扩张。宫颈改变是正常分娩的重要元素。观察发现，宫颈的变化除了包括胶原断裂和重组，还有葡胺聚糖的变化，细胞因子产物的增加，以及白细胞的浸润。如果有引产指证，而宫颈条件还不合适，就该使用促宫颈成熟的药物。宫颈条件可以用Bishop骨盆评分系统来进行评估（表1）。大量随机试验表明，不合适的宫颈按照Bishop评分大概是6分或6分以下。如果总分大于8，引产后阴道分娩的可能性与自发宫缩分娩是类似的。
Table 1. Bishop Scoring System
有效的宫颈成熟方法包括使用机械性宫颈扩张器和合成前列腺素E1（PGE1）和前列腺素E2（PGE2）。机械性扩张的方法对宫颈的成熟是有效的，包括吸湿性扩张器，渗透性扩张器(Laminaria japonicum)，带有30-80ml气囊的Foley导管（14-26F），双球器(Atad Ripener Device)，和用盐水以30-40ml/h速度进行羊膜外注射。Laminaria japonicum使宫颈成熟可能伴发围产期感染的增加。宫颈不成熟而进行引产的妇女，除了羊膜外盐水注入，其他机械性方法和仅用催产素相比，都伴有剖宫产率的增加。多项研究表明了机械性宫颈扩张的疗效。评价机械方法和前列腺素对比的有效性（26小时内阴道分娩）尚缺乏足够证据。Foley导管的优势包括，与前列腺素相比的低成本，室温下的稳定性，降低了子宫过度收缩的风险，伴或不伴胎心率的变化。
米索前列醇，一种合成的PGE1类似物
，可以用来上阴道、口服，或舌下含化，可以用来促宫颈成熟和引产。目前用100mcg（μg）或200mcg的片剂，可分为25mcg或50mcg的量使用。广泛的临床经验以及大量已发表文献证实了合理使用该药的安全性及疗效。尚无研究表明，产时米索前列醇（或其他促宫颈成熟的前列腺素药物）在无胎儿窘迫