Doret M, Pasquier J-C, Gharib C, Gaucherand P
Département de gynécologie-obstétrique, hospices civils de Lyon, hôpital Edouard-Herriot, place d'Arsonval, Lyon cedex 03, France.
J Gynecol Obstet Biol Reprod (Paris). 2008 Feb;37(1):24-32. doi: 10.1016/j.jgyn.2007.08.005. Epub 2007 Nov 26.
Preterm labour diagnosis rely on clinical arguments exhibiting low positive predictive values. Discrimination between uterine contractions leading to preterm delivery and physiologic uterine activity increase throughout pregnancy and remains difficult. Uterine electrical activity can be recorded non-invasively from the abdominal wall and could help in the diagnosis of preterm labour. Electrical signal characteristics are reflecting myometrial cells electrical properties which are varying throughout pregnancy and labour. During pregnancy, uterine electrical activity is very low. During term and preterm labour, uterine electrical activity increases as well as mechanical activity. Bursts become regular with high amplitude. Spectral analysis demonstrates an increase in the frequency content, as represented by the shift of the burst power density spectrum peak frequency from low to high frequencies. Consequently, the electromyogram signal reflects myometrial excitability and allows differentiating powerful uterine contractions leading to delivery from uterine physiologic activity. Moreover, electromyogram signal modifications occur before any increase in mechanical activity in the pregnant rats, allowing identification of preterm labour earlier than uterine mechanical activity measured by intrauterine pressure. Two studies performed in women present with preterm contractions are supporting the potential interest of the uterine electromyogram recording to help in the diagnosis of preterm labour; but further investigations are necessary.
早产的诊断依赖于临床依据，而这些依据的阳性预测值较低。区分导致早产的子宫收缩与整个孕期生理性子宫活动的增加仍然很困难。子宫电活动可以从腹壁进行无创记录，这可能有助于早产的诊断。电信号特征反映了子宫肌层细胞的电特性，这些特性在整个孕期和分娩过程中会发生变化。在孕期，子宫电活动非常低。在足月和早产时，子宫电活动以及机械活动都会增加。爆发变得规律且幅度增大。频谱分析表明频率成分增加，这表现为爆发功率密度谱峰值频率从低频向高频的转变。因此，肌电图信号反映了子宫肌层的兴奋性，并能够区分导致分娩的强烈子宫收缩与子宫生理性活动。此外，在怀孕大鼠中，肌电图信号的改变在机械活动增加之前就会出现，这使得早产的诊断能够比通过宫内压力测量的子宫机械活动更早地进行。两项针对有早产宫缩的女性进行的研究支持了子宫肌电图记录在帮助诊断早产方面的潜在价值；但仍需要进一步的研究。
