Strengths and limitations
In our study we recruited a large sample size in the final analysis, which can reduce the bias and provide the decent comparisons in different study groups. And we applied the modified Glazer protocol to evaluate the signal data of pelvic floor sEMG, which demonstrated the precise scale and detailed type of PFM in dysfunction based on a quantitative approach. It is powerful to support the comprehensive and accurate analysis on the impact on PFM function by different deliveries at the early postpartum stage.
Our study also has several limitations. Firstly, our study is hospital-based, it contains selective bias. Secondly, due to the small sample size of third-degree perineal lacerations, we did not have enough power to analyze the third-degree perineal lacerations in vaginal delivery. Finally, since this study only evaluated pelvic floor sEMG at 6-8 weeks postpartum, it may not be sufficient for accessing final pelvic muscle function. Therefore, a long-term follow-up epidemic study is further suggested.