The Reliability, Practicality and Acceptability of Using Ultrasonography to Monitor the Progress of Labour and Delivery

Introduction: It had been suggested by a number of recent studies that ultrasonography could become an alternative to digital vaginal examination (VE) for assessing the progress of pregnant women in labour. However, no systematic review and meta-analysis on the effectiveness of ultrasonography was available. Systematic Review: A systematic review and meta-analysis was conducted to investigate the success rate of ultrasonography in comparison with digital VE and the level of agreement between the two methods, in terms of estimating fetal head position, head station and cervical dilatation. Systematic Review Findings: This review found that ultrasonography has a higher success rate than digital VE in estimating fetal head position. Ultrasonography was also in high agreement with digital VE in estimating cervical dilatation, with insignificant difference in the success rate of the two methods in terms of detecting cervical dilatation. There was also a significant correlation between the two methods in estimating head station. However, it was also found by the review that, existing primary studies were mainly conducted in tertiary settings of developed countries. Further research was therefore needed from the perspective of non-tertiary settings and also from developing country settings. In addition, further research was also needed to assess the diagnostic performance of ultrasound in detecting active labour, since it is associated with cervical dilatation. The diagnostic performance of ultrasound in detecting engaged fetal head had also not been investigated, which is necessary because it is associated with head station. Primary Research Aim: As a consequence of these systematic review findings, a primary study was conducted in another clinical setting in a developing country. The aim was to investigate the reproducibility, practicality and acceptability of using ultrasonography to monitor the progress of pregnant women in labour. Research Methods: A cross-sectional study was conducted in a teaching hospital in Ghana. The agreement between ultrasound and digital VE was statistically analysed for the estimation of fetal head position, head station and cervical dilatation. Further statistical analysis was conducted on the diagnostic performance of ultrasound in detecting engaged fetal head, and the diagnostic performance of ultrasound in detecting active labour. A quantitative survey of mothers’ acceptance of intrapartum ultrasound was also conducted. Lastly, caregivers’ views on the practicality of using ultrasound in this developing country setting was also investigated in a qualitative survey. Results of Primary Research: The results regarding reproducibility were as follows: (i) a high between-method agreement was found in the estimation of cervical dilatation, with high ultrasound sensitivity and specificity in detecting active labour; (ii) a statistically significant between-method agreement was found in the estimation of head station, with high ultrasound sensitivity and specificity in detecting engaged fetal head; (iii) a weak between-method agreement was found in the estimation of fetal head position, with ultrasound having a higher success rate than digital VE. The results regarding acceptability showed that most mothers accepted the use of intrapartum ultrasound, and were willing to have the procedure for their future care during labour and childbirth. They also preferred ultrasound to digital VE. With regards to practicality, the responses of caregivers indicate that the introduction of intrapartum ultrasound in this setting could serve as a good complement to digital VE in a number of ways. However, putting it into practice would require wider availability of physical and technical resources. Conclusion: The findings of the reproducibility study were consistent with existing studies in other clinical settings which were investigated in the systematic review. This suggests that ultrasound is a reliable method for assessing the progress of pregnant women in labour. In addition, the unique contribution to existing knowledge obtained from this study was a high ultrasound sensitivity and specificity in detecting active labour and engaged fetal head which were reported for the first time. The findings on mothers’ acceptability were also consistent with existing studies in other settings, which is an indication that there is high acceptance of intrapartum ultrasound by mothers from different settings and cultures. Lastly, caregivers’ views on the practicality of the use of ultrasound during labour indicate that the regular use of intrapartum ultrasound for assessing the progress of labour in pregnant women may require additional resources to make it practicable in this and other similar settings.