The T/QRS ratio values in pregnancies complicated by threatened preterm labour treated with intravenous infusions of fenoterol

Abstract

AbstractTo evaluate values of foetal T/QRS ratios in pregnancies complicated by threatened preterm labour treated with intravenous infusions of fenoterol using non-invasive methods with transabdominal electrodes.The study group consisted of 451 Caucasian women (63 preterm pregnancies and 327 healthy controls) whose pregnancies ranged from 28 to 37 gestational weeks. Foetal electrocardiograms were recorded and T/QRS ratios were calculated by KOMPOREL software (ITAM, Zabrze, Poland). The first recording was performed 30 min after the start of fenoterol infusion and the second 2 days after finishing tocolysis. T/QRS ratio variables were calculated. One-way analysis of variance was carried out.Significantly higher mean values of the T/QRS ratio were observed in pregnancies during tocolytic treatment in comparison to controls and pregnancies after tocolysis (P=0.0158 and P=0.0071, respectively). The T/QRS ratio values fall again shortly after finishing intravenous tocolysis.The T/QRS ratio is one of the methods used for non-invasive foetal distress assessment that can be used in antepartum foetal monitoring in complicated pregnancies. Raised values of the T/QRS ratio in the foetus during tocolysis with fenoterol and next its fall to values observed in physiological pregnancies may indicate transient worsening of fetal well-being, however, additional research is required.