Comparison of Digital Vaginal Examination with Intrapartum Transabdominal Ultrasound to Determine Fetal Head Position: a Local Experience

Abstract

Objective: To investigate the accuracy of intrapartum digital vaginal examination in assessing fetal head position during active labour, and to compare accuracy of intrapartum digital vaginal examination for fetal head position between specialist trainee doctors and specialist obstetricians.
Methods: A total of 100 patients at term with normal singleton cephalic-presenting fetuses were recruited.
Transabdominal ultrasound examination to determine the position of the fetal head was performed by a trained sonographer, followed immediately by digital vaginal examination by attending specialist trainee doctor or specialist obstetrician. Both examiners were blinded to each other’s findings. A total of 112 measurements were generated. Statistical analyses included Chi-square test, Kappa test, and logistic regression analysis. p Values of <0.05 were considered statistically significant.
Results: Digital vaginal examinations were completely consistent with ultrasound assessment in 34 (30%) cases. Assuming that the fetal head position was correct provided it was within ± 45 degrees of the ultrasound assessment, digital examination was accurate in 77 (69%) of cases. The respective rate of agreement between the two assessment methods by specialist trainee doctors versus specialist obstetricians was 67% and 75% (p=0.69). There were no significant associations between accuracy of digital vaginal examination and maternal and labour characteristics.
Conclusions: Fetal head position during active labour determined by digital vaginal examination was accurate in about two-thirds of all cases, with only one-third of cases being in complete agreement with that obtained by ultrasound assessment. There was no statistically significant difference in accuracy of digital vaginal examination by specialist trainees compared with that by specialist obstetricians.