Transperineal ultrasound. An objective and efficient method to assess fetal head descent in the second stage of labor

L. Ples, M. Burtea, R. Sima

Abstract: The aim of this study was to identify patients who will undergo vaginal delivery or cesarian section correlating clinical station with transperineal ultrasound (TPU) measurements during the second stage of labor. Our study included 88 laboring patients with unique, term pregnancies and cranial presentation which were clinically and by TPU examined. TPU appreciated fetal head descent measuring the angle between the longitudinal axis of the pubic symphysis and a tangential axis to the fetal skull. Intra- and inter-examiner variability was noticed. A significant associatin was noticed between digital examination and the angle of fetal head descend. An angle of at least 120⁰ during the second stage of labor was associated with vaginal delivery. Six cases of caesarean section resulted in average angle of descent of 108⁰. Our data sugest that TPU measurement of progression angle can be an objective method for estimating with accuracy and reproducibility the descent of fetal head.
Keywords: transperineal ultrasound, fetal head descent, progression angle, digital examination