Control and assessment of the uterus and cervix during pregnancy and labour
Control and assessment of the uterus and cervix during pregnancy and labour
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DOI：
10.1093/humupd/4.5.673
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发表时间：
1998-09-01
影响因子：
13.3
通讯作者：
Chwalisz, K
中科院分区：
文献类型：
--
作者：
Garfield, RE;Saade, G;Chwalisz, K
早产和由此产生的早产是围产学中最重要的问题。无数的努力都未能建立单一有效的早产治疗方法，部分原因是对怀孕期间调节子宫和宫颈的机制没有很好的了解。需要新的知识来抑制分娩的早期进展(子宫收缩和宫颈成熟)，缺乏足够的量化工具来评估怀孕期间的子宫和宫颈。在这篇综述中，我们概述了显示子宫(子宫肌层)和宫颈在为分娩做准备的过程中经历了一个条件步骤的研究。这一步骤很难用目前评估子宫或宫颈的方法来识别，在子宫中，这一看似不可逆转的步骤包括使肌肉更具兴奋性和响应性的电特性变化，以产生强有力的收缩。在宫颈，这一步骤包括结缔组织成分的软化，孕酮似乎在控制子宫和宫颈方面起主导作用，因为抗孕激素诱导早期的、早产的条件反射导致早产。显然，一氧化氮(NO)也控制着子宫和宫颈的调节，在子宫中，NO与黄体酮一起抑制子宫收缩。在足月，子宫和胎盘的NO产量减少，并允许分娩进展，相比之下？宫颈中的NO在妊娠末期升高，这可能是通过激活金属酶刺激宫颈成熟的最终途径，可以使用从腹部表面记录的子宫前方肌电(EMG)信号来无创性地评估产程进展。以这种方式检测到的子宫肌电爆发是人类和动物怀孕期间子宫收缩事件的特征。子宫肌电活动较低，在分娩过程中，子宫肌电活动显著增加。在人类和大鼠的早产过程中，肌电活动也会大幅增加。这种方法有朝一日可能被用来预测即将到来的早产，并确定控制措施和治疗方法。一种定量的方法也评估宫颈，使用光学设备测量宫颈中的胶原蛋白荧光。当用大约340mN的激发光照射胶原交联物时产生的荧光信号，胶原镜从产生的荧光信号中估计宫颈胶原含量，该系统已被证明对怀孕不同阶段的大鼠和人类有用，并表明宫颈软化在妊娠的最后三分之一逐渐发生。在大鼠中，镜读数与在隔离宫颈中进行的阻力测量相关，这可能有助于评估怀孕期间的宫颈功能，并指示控制和治疗。
Preterm labour and resultant preterm birth are the most important problems in perinatology. Countless efforts have failed to establish a single effective treatment of preterm labour, partly because the mechanisms regulating the uterus and cervix during pregnancy are not well understood. New knowledge is needed to inhibit early progression of labour (uterine contractility and cervical ripening), and adequate quantitative tools to evaluate the uterus and cervix during pregnancy are lacking. In this review we outline studies showing that the uterus (myometrium) and cervix pass through a conditioning step in preparation for labour. This step is not easily identifiable with present methods to assess the uterus or cervix, In the uterus, this seemingly irreversible step consists of changes in the electrical properties to make muscle more excitable and responsive to produce forceful contractions, In the cervix, the step consists of softening of the connective tissue components, Progesterone appears to have a dominant role in controlling both the uterus and cervix, as antiprogestins induce early, preterm conditioning leading to preterm labour. Apparently, nitric oxide (NO) also controls conditioning of the uterus and cervix, Ire the uterus, NO, in concert with progesterone, inhibits uterine contractility. At term, NO production by the uterus and placenta are decreased and allow labour to progress, in contrast? NO in the cervix increases at the end of pregnancy and it may be the final pathway for stimulating cervical ripening by activation of metalloenzymes, The progress of labour can be assessed non-invasively using electromyographic (EMG) signals front the uterus (the driving force for contractility) recorded from the abdominal surface. Uterine EMG bursts detected in this manner characterize uterine contractile events during human and animal pregnancy. A low uterine EMG activity, measured transabdominally throughout most of pregnancy, rises dramatically during labour. EMG activity also increases substantially during preterm labour in humans and rats. This method may be used one day to predict impending preterm labour sand identify control steps and treatments. A quantitative method also assesses the cervix, using an optical device which measures collagen fluorescence in the cervix. The collascope estimates cervical collagen content from a fluorescent signal generated when collagen cross-links are illuminated with excitation light of about 340 mn, The system has proved useful in rats and humans at various stages of pregnancy, and indicates that cervical softening occurs progressively in the last one-third of pregnancy. In rats, collascope readings correlate with resistance measurements made in the isolated cervix, which may help to assess cervical function during pregnancy, and indicate control and treatments.