Severe cardiotocographic pathology at labor: effect of acute intravenous tocolysis.

The purpose of this study was to evaluate the effect of acute tocolysis on severely pathological cardiotocographic (CTG) readings during the first stage of labor. Seventy-three consecutive parturients with full-term pregnancy were treated by acute tocolysis with a beta-mimetic agent after recognition of severe CTG abnormality in the first stage of labor. The main outcome measures were normalization or persistence of the CTG pattern after tocolysis. Risk factors with regard to CTG effect of tocolysis were also evaluated. In 67% of cases the CTG pattern normalized at a mean of 4 minutes after the beginning of intravenous tocolysis. No characteristic feature of the parturient, labor course, CTG abnormality, or the parameters of uterine contractive activity was found to be a predictive factor with regard to the CTG effect of tocolysis. No adverse effects of tocolytic therapy were found. Tocolysis with a beta-mimetic agent is an effective method to normalize the CTG pattern during the first stage of labor, even in cases without uterine hypertonicity.