Systematic review and meta-analysis: gray-scale ultrasound and shear wave elastography in the diagnosis of primipara pregnancy and delivery.

BACKGROUND

The combination of shear wave elastography (SWE) and gray-scale ultrasound is widely used in the measurement of female pelvic floor muscle. However, the value of gray-scale ultrasound combined with SWE in the evaluation of primipara pregnancy and delivery is still controversial.

METHODS

Using the PubMed, Web of Science, Spring and Science Direct databases, clinical studies on gray-scale ultrasound combined with SWE on the diagnosis of primiparous pregnancy and childbirth published from January 2010 to December 2020 were searched. The RevMan5.3 software was used to conduct a meta-analysis of the indicators of gray-scale ultrasound combined with SWE for primiparas and non-primiparas, including: age, body mass index (BMI), gestational age at examination, gestational age at delivery, fetal weight, cervical length, shear wave velocity (SWV), front lip SWV, back lip SWV, Young's modulus and SWE index. Heterogeneity of the assessment results was tested using Cochran's chi-square.

RESULTS

A total of 13 articles were included. Age, BMI before delivery, gestational age (when gray-scale ultrasound was combined with SWE examination), gestational age at delivery, neonatal weight, cervical depth, SWV of placental margin, SWV of anterior lip, SWV of posterior lip and Young's modulus of the study group were significantly different from those of the control group. The elastic modulus of the perineal body and the SWE of the anterior lip of the study group were significantly higher than those of the control group [mean difference (MD) =8.11, 4.39, 95% confidence interval (CI): 3.90-12.31, 0.94-7.83; Z=3.78, 2.49, P=0.0002, 0.01]. The SWE of the posterior lip in the study group was significantly lower than that in the control group (MD =-4.34, 95% CI: -7.23 to 1.44; Z=2.93, P=0.003).

DISCUSSION

The number of cases in the control group in the included articles was significantly more than that in the observation group, and there were fewer descriptions of gray-scale ultrasound combined with SWE indicators in the included articles. There may be a certain degree of bias for indicators without obvious heterogeneity, and further analysis was required through a large number of clinical verifications. However, this study can provide certain reference values for the diagnosis of primipara pregnancy.