Effect Of Different Delivery Methods On Pelvic Floor Muscle Strength In Women In The Early Postpartum Period

Objective: China’s family planning policy advocates eugenics,yet the adverse effects of childbirth and other factors on pelvic floor muscle strength compromise women’s physical and psychological health.Unfortunately,experts and scholars at home and abroad have not yet reached a consensus on the conclusive view of the effect of different delivery methods on pelvic floor muscle strength.In this paper,based on this debate,we investigate the effects of different delivery methods on pelvic floor muscle strength in the early postpartum period,which can help to detect,treat and prevent postpartum pelvic floor dysfunctional diseases in women,and is important for improving the quality of women’s postpartum life,promoting family and social harmony and guiding the scientific selection of delivery methods.Methods: 203 women were selected according to the inclusion criteria.They were divided into perineal Ⅰ degree laceration group,perineotomy group,forceps assisted delivery group,elective caesarean section group and intermediate caesarean section group.The required data were collected and data were processed using SPSS Statistics 26.0software,with the count data expressed as(n%)and the measurement data as((?)±s).Oneway ANOVA was used for comparison between groups,and logistic regression analysis was used to assess other obstetric factors The difference was statistically significant if P<0.05.Results: There were no statistically significant differences between two comparisons of weight gain,number of pregnancies and blood glucose values between the study subjects,with P values > 0.05.Comparing the mean values of EMG at each stage of the different delivery methods,the mean values of EMG at each stage of cesarean delivery were higher than those of vaginal delivery;the mean values of EMG at each stage of forceps assisted delivery were the lowest;and the mean values of EMG at the slow muscle stage were lower than normal.The mean values for the pre-resting and post-resting phases were higher than those for vaginal delivery and normal values for both intermediate and elective caesarean deliveries.When comparing the proportion of myoelectric values at each stage of labour with those of the under-normal and over-myoelectric types,the proportion of normal myoelectric values was below 40% for all delivery methods;the proportion of undermyoelectricity was less in cesarean delivery than in vaginal delivery;and the proportion of forceps-assisted delivery was lowest in the over-myoelectric group.In linear regression analysis,no significant differences were found for perineotomy compared to perineal Ⅰ laceration(all P>0.05),there was a significant effect of forceps assisted labour on EMG values in the fast and slow muscle phases(correlation coefficients β=-10.79,P=0.001 and β=-6.14,P=0.006,respectively),and both elective and intermediate cesarean deliveries had a significant effect on anterior resting phase EMG values(correlation coefficients β=1.64,P=0.03;β=1.96,P=0.004,respectively),slow muscle phase EMG values(correlation coefficients β=6.88,P=0.01;β=5.88,P=0.02,respectively)and post resting phase EMG values(correlation coefficientsβ=1.95,P=0.03;β=1.78,P=0.005,respectively));after including also the independent variables of maternal age,gestational week,prenatal BMI,anterior resting phase EMG,gestational weight gain,neonatal birth weight,whether labour was induced and whether gestational diabetes was present,forceps assisted delivery still had a significant effect on fast and slow muscle phase EMG(correlation coefficients β=-8.95,P=0.01;β=-5.39,P=0.01),and elective and intermediate caesarean sections still had a significant effect on anterior resting phase EMG values(correlation coefficients β=2.47,P=0.01;β=1.85,P=0.01,respectively).Pre-resting phase EMG values significantly affected fast,slow and post-resting phase EMG values(correlation coefficients β=2.13,P<0.001;β=1.19,P<0.001;β=0.84,P<0.001 respectively),indicating that higher pre-resting phase EMG values lead to higher fast,slow and post-resting phase EMG values.In univariate regression analysis after dichotomisation(normal and abnormal),there was a significant effect of intermediate caesarean section on the anterior resting and fast muscle phases compared to perineal Ⅰ laceration(OR=3.38,P=0.03;OR=0.27,P=0.01,respectively)and a significant effect of elective caesarean section on the fast muscle phase(OR=0.36,P=0.047,respectively)When the other factors mentioned above were also taken into account,elective cesarean delivery,intermediate cesarean delivery and maternal age were found to be significantly associated with anterior resting phase EMG(OR=4.58,P=0.03;OR=10.71,P=0.001;OR=1.14,P=0.04;OR=5.97,P=0.001,respectively)and antepartum BMI had a significant effect on fast muscle phase EMG values(ratio OR=1.16,P=0.03,respectively);preresting phase EMG values had a significant effect on post resting phase EMG values(ratio OR=1.27,P<0.001,respectively).Conclusions: 1.Birth can damage pelvic floor muscle strength to varying degrees.Cesarean delivery has a protective effect on pelvic floor muscle strength compared with vaginal delivery,but cesarean delivery causes resting muscle tension in the pelvic floor muscles,so cesarean delivery does not completely prevent pelvic floor muscle strength damage.2.Among cesarean deliveries,the effect of elective cesarean delivery on pelvic floor muscle strength is less than that of intermediate cesarean delivery,but the difference is not significant,so the evidence that elective cesarean delivery protects pelvic floor muscle strength is still insufficient.3.In vaginal birth,perineal incision and first-degree perineal laceration have comparable effects on pelvic floor muscle strength,so routine perineal incision is not recommended to protect pelvic floor muscle strength;forceps can reduce pelvic floor muscle strength,so the use of forceps to assist labour should be strictly indicated and the appropriate type of instrument should be selected by an experienced practitioner to reduce side effects.4.Age of the woman is a risk factor for injury to the pelvic floor muscle tone in the resting phase before delivery;BMI before delivery is a risk factor for injury to the muscle strength of class Ⅱ muscle fibres.