Assessing the Risk of Spontaneous Premature Birth by Electrical Impedance Spectroscopy of the Cervix.

出生的时间对繁殖至关重要。大约6-13%的婴儿早产，NHS每年要比足月婴儿多花费10亿英镑。存活的早产儿第一年的护理费用是足月婴儿的10倍。早产（PTB）也是造成结构正常婴儿死亡的主要原因。在28周前出生的婴儿中，有四分之一患有残疾，这给家庭带来了社会经济负担，许多父母经常不得不放弃工作来照顾孩子。由于缺乏准确的风险预测，结核病的预防受到限制。我们的研究小组一直在探索电阻抗谱（EIS）技术，通过记录宫颈组织的电阻率（即宫颈阻抗）来评估宫颈组织的成分。我们的想法是，如果我们能在分娩前几个月检测到子宫颈发生的变化，我们就能预测女性是否会早产。为了验证这一理论，我们最近进行了一项小规模的试点研究。在一小群有早产风险的妇女中（因为她们之前有过早产），我们最近发现EIS有望准确预测早产——37周之前分娩的妇女，以及34周之前分娩的妇女，在20到28周之间的宫颈阻抗比那些没有早产的妇女低。我们现在建议通过更大规模的研究来证实这些初步发现。首先，我们将改进EIS的测量装置，使其与子宫颈的接触标准化，并改进其硬件和软件。然后，我们将在怀孕期间的两个时间点（22周和26周）对两组孕妇（250名有早产危险因素的妇女）进行一项大型实验研究，测量宫颈阻抗。我们将寻求确认在临床护理中使用EIS将提高我们预测、预防和治疗早产和分娩的能力。我们将比较EIS与目前的筛查方法，如纤维连接蛋白试验和宫颈超声。我们还将对其引入临床护理进行一些初步的成本分析，并确定与目前的标准护理相比，它是否具有成本效益。人们普遍认为自发性PTB通常与子宫感染和炎症有关，但这种关联的机制和模式尚不清楚。利用现代技术分析阴道内的细菌，我们将探讨早产妇女阴道分泌物中的细菌模式与足月分娩妇女阴道分泌物中的细菌模式是否有显著差异。通过发现这一点，我们可以将一种诊断试剂盒推向市场，该试剂盒可以检测与随后的PTB最相关的模式，结合宫颈EIS测量，可以提高我们对PTB的预测。通过我们的研究，及时和改进对肺结核风险的识别将有助于提供更好的护理。这可以通过服用诸如黄体酮之类的药物，或其他已知可以延长妊娠的止痛药物来实现。它还可以帮助我们识别“弱”子宫颈，这是一种无法准确诊断的情况，因此可以更适当地在那些真正需要的人的子宫颈周围插入一针，而避免在那些不需要的人身上插入一针。对于有早产症状的妇女，宫颈EIS可以很好地识别出那些比其他人更有可能分娩的妇女，以便提供治疗，使婴儿的肺部为分娩做好准备，推迟分娩，或确保在人员配备和设备适当的保健设施中分娩。大多数早产发生在没有危险因素的妇女身上。目前还没有准确的方法对所有女性进行筛查。因此，我们建议在250名低危妇女中也测量22周宫颈EIS，以确定它是否可用于所有孕妇PTB风险的常规筛查。

The timing of birth is crucial to reproduction. About 6-13% of babies are born prematurely at annual costs to the NHS of £1 billion more than for term babies. The cost of care in the first year of life for the surviving premature baby is 10-fold higher than for the term baby. Preterm birth (PTB) also accounts for the majority of deaths of structurally normal babies. A quarter of babies born before 28 weeks suffer handicap, with socio-economic burdens on families, many parents often having to give up work to care for their child. Prevention of PTB is limited by lack of accurate prediction of risk. Our group has been exploring the technique of electrical impedance spectroscopy (EIS) for assessing cervical tissue composition by recording its electrical "resistivity" - cervical impedance - to the injection of a small electrical current. Our thinking is that if we can detect the changes which occur in the cervix several months before labour starts we can predict women who will go into premature labour.To test out this theory we recently conducted a small pilot study. In a small group of women at risk of premature birth (because they have had premature births before), we recently showed that EIS holds promise for accurately predicting premature delivery - women who delivered before 37 weeks, as well as those who delivered before 34 weeks, had lower cervical impedance between 20 and 28 weeks than those who did not. We now propose to confirm these preliminary findings by larger studies. Firstly, we will improve the measuring device for EIS by standardising its contact to the cervix and improving its hardware and software. We will then undertake a large experimental study measuring cervical impedance in two groups of pregnant women - 250 women with risk factors for preterm birth - at two time points during pregnancy (22 and 26 weeks). We will seek to confirm the use of EIS in clinical care will improve our ability to predict, prevent, and treat preterm labour and birth. We will compare EIS to current screening methods such as the fibronectin test and cervical ultrasound. We will also undertake some preliminary cost analysis of its introduction into clinical care and determine whether it may prove cost-effective compared to standard current care.It has been well recognised that spontaneous PTB is often associated with uterine infection and inflammation but the mechanism and pattern of this association is unclear. Using modern techniques of profiling bacteria in the vagina we will explore whether the bacterial pattern in vaginal discharge of women who deliver preterm differs significantly from that of women who deliver at term. By finding this out we may be able to market a diagnostic kit which detects the pattern most associated with subsequent PTB which, combined with cervical EIS measurement, may improve our prediction of PTB. Prompt and improved identification of PTB risk by our studies will enable better care. This is possible through the administration of drugs such as the hormone progesterone, or others within the family of pain relief medication, known to prolong pregnancy. It may also help us to identify the "weak" cervix, a condition that continues to defy accurate diagnosis, so that a stitch can be more appropriately inserted round the cervix of those that truly need this, and avoided in those that do not need this. For women with symptoms of preterm labour cervical EIS may well identify those who are more likely to progress to birth than others, so that treatments to prepare the baby's lungs for birth, delay the birth, or ensure that birth occurs in an appropriately staffed and equipped health care facility can be provided. Most preterm births occur in women with no risk factors. At present there is no accurate method of screening all women. We therefore propose to measure cervical EIS at 22 week in 250 low risk women also, to determine whether it can be used for routine screening of all pregnant women for risk of PTB.