Comparative Analysis of Pelvic Floor Muscle Damage Postpartum: Vaginal Delivery vs. Cesarean Section

Background. Evaluation of pelvic floor muscle (PFM) strength damage across different delivery modes, providing insights into potential preventive measures for pelvic floor dysfunctions (PFDs) in the early postpartum period. Aim. Compare the differences in PFM strength and endurance between full-term cesarean section (CS) and vaginal delivery (VD) in the early postpartum period of primiparous women. Methods. The assessment included stress urinary incontinence (SUI), pelvic organ prolapse (POP), and pelvic floor electromyography (PFE). Muscle fiber strength was categorized into four modes at a threshold level of 3: I < 3 II < 3, I < 3 II > 3; I > 3 II < 3, I > 3 II > 3. Multinomial logistic regression was employed for CS and VD, and a sensitivity analysis was conducted using level 2 as the threshold. Outcomes. When muscle fiber strength was categorized into four modes at a threshold level of 3, Type I, and Type II fiber muscle endurance (FME) are differences between the CS and VD groups. Results. The CS and VD groups differed significantly in SUI and anterior and posterior vaginal wall conditions. MDVP was below the normal range in both groups, and MDVP, PFM strength, and PFM endurance did not differ significantly (P > 0.05). Logistic regression results indicated that higher MDVP, Type I, and Type II FME were protective factors when I < 3 in the VD group. However, I < 3-II > 3, higher MDVP, and Type I FME were protective factors (OR: 0.339, 95% CI: 0.223, 0.516) in the CS group. Clinical Implications. The study introduces a nuanced understanding of the impact of different delivery modes on PFM, contributing valuable insights for clinical prevention and treatment strategies in the early postpartum period. Strengths and Limitations. Muscle fiber strength was categorized into four modes and further sensitivity analysis was conducted. This study only conducted a correlation analysis of outcome variables without considering intervenable variables. Conclusions. The VD group had a higher incidence of pelvic floor dysfunction in the early postpartum period than the CS group. Both groups experienced a decline in PFM function without significant differences. CS was primarily associated with Type I muscle fiber damage, while VD was related to both Type I and II muscle fiber damage. Improving PFM endurance is beneficial for muscle strength recovery.