Levator ani muscle injury and risk for urinary and fecal incontinence in parous women from a normal population, a cross‐sectional study

The predicting value of the ratio of levator hiatus diameter to fetal head circumference in pregnant women at 37 weeks of gestation in the progression of the second stage of labor and levator ani injury 6 weeks postpartum

Objective

This study investigated the predicting value of the ratio of levator hiatus diameter (LHS) to fetal head circumference (HC) in pregnant women at 37 weeks of gestation in the progression of the second stage of labor and levator ani injury 6 weeks postpartum.

Methods

A total of 120 first-time women who gave vaginal delivery at 37 weeks of pregnancy were selected as the subjects in our hospital during March 2021 to March 2022. The subjects were divided into the second stage of labor > 1 h group and the second stage of labor ≤ 1 h group, according to the delivery time of the second stage of labor. According to the 6-week postpartum follow-up ultrasound examination with or without levator ani injury, they were divided into levator ani injury group and no injury group. All primipara women underwent three-dimensional ultrasonography at 37 weeks of gestation, and the resting LHS, Valsalva LHS, fetal HC and the ratio of resting LHS and fetal HC were compared. The correlation between these factors and the length of the second labor stage was analyzed using Pearson correlation analysis. The value of these factors in predicting labor progression and postpartum levator ani injury was assessed by receiver operating characteristic (ROC) curves.

Results

The resting LHS, Valsalva LHS and the ratio of resting LHS and fetal HC in the levator ani injury group were lower than these in the no injury group, while fetal HC in the levator ani injury group was higher than that in the no injury group (P < 0.05). The resting LHS, Valsalva LHS and the ratio of resting LHS and fetal HC in the second stage of labor > 1 h group were lower than these in the second stage of labor ≤ 1 h group, while fetal HC in the second stage of labor > 1 h group was higher than that in the second stage of labor ≤ 1 h group (P < 0.05). A significant negative correlation was observed between resting LHS/HC and total labor process (=-0.333, P < 0.01). ROC curve analysis showed that the AUCs of resting LHS, Valsalva LHS, HC, and resting LHS/HC ratio in predicting prolongation of the second stage of labor were 0.741, 0.740, 0.702, and 0.843 respectively. Besides, the AUCs of resting LHS, Valsalva LHS, HC, and resting LHS/HC ratio in predicting the total labor process were 0.657, 0.684, 0.768, and 0.836 respectively. The AUCs of resting LHS, Valsalva LHS, HC, and resting LHS/HC ratio in predicting postpartum levator ani muscle injury were 0.769, 0.773, 0.747, and 0.885 respectively.These results suggested that the ratio of resting LHS and fetal HC may have certain clinical value in predicting levator ani injury in pregnant women.

Conclusion

LHS, fetal HC and the ratio of resting LHS and fetal HC are significantly correlated with labor progression and postpartum levator ani injury, which have certain value in predicting labor progress and postpartum levator ani injury. Therein, the ratio of resting LHS and fetal HC has the highest predictive value, and early detection of the ratio of resting LHS and fetal HC is helpful to guide the selection of appropriate delivery mode.

Unilateral levator avulsion increases the risk of de novo stress urinary incontinence after cystocele repair

INTRODUCTION

Patients without concurrent baseline stress urinary incontinence (SUI) can develop de novo SUI after transvaginal mesh surgery (TVM) for cystocele repair. Surgeons should be aware of de novo SUI risk factors after TVM.

METHODS

A total of 1124 women who were underwent TVM surgeries were recruited and assessed for eligibility from January 1, 2012 to April 30, 2021. All data related to patients and surgeries was collected, which included general conditions, clinical examination, surgery records, and follow-up results. Patients were divided into three groups according to follow-up results and data were compared with each group. The relative risk (RR) of de novo SUI with levator avulsion was also calculated.

RESULTS

Three hundred thirty-six patients were included in this study. They were divided into no complication group (n = 249), de novo SUI group (n = 68), and other complications group (n = 19). It seemed elder or obese women had a higher risk of de novo SUI after TVM (p < 0.05). In de novo SUI group, incidence of levator avulsion before surgery were higher than the other two groups (p = 0.001). TVM can significantly change a prolapse to point Aa and Ba on POP-Q quantification system (p < 0.05). RR ratios of de novo SUI with unilateral avulsion group is 2.60 (95% confidence interval [CI] 1.39-4.87), and 2.58 (95%CI 0.82-8.15) for bilateral group.

CONCLUSION

Unilateral levator avulsion, instead of bilateral levator avulsion, is a risk factor of de novo SUI after cystocele repair surgery.

Diagnosis of maternal birth trauma by pelvic floor ultrasound

BRIEF SUMMARY

Maternal somatic birth trauma due to vaginal delivery is more common than generally assumed and an important cause of future morbidity. Maternal birth trauma may involve both psychological and somatic morbidity, some of it long-term and permanent. Somatic birth trauma is now understood to encompass not just episiotomy, perineal tears and obstetric anal sphincter injuries (OASI), but also trauma to the levator ani muscle, termed 'avulsion'. This review will focus on recent developments in the imaging diagnosis of maternal birth trauma, discuss the most important risk factors and strategies for primary and secondary prevention. Translabial and exo-anal ultrasound allow the assessment of maternal birth trauma in routine clinical practice and enable the use of levator avulsion and anal sphincter trauma as key performance indicators of maternity services. This is likely to lead to a greater awareness of maternal birth trauma amongst maternity caregivers and improved outcomes for patients, not the least due to an increasing emphasis on patient autonomy and informed consent in antenatal and intrapartum care.

Secondary urethral sphincter function of the rabbit pelvic and perineal muscles

Perineal and pelvic floor muscles play an important role in continence by providing mechanical support to pelvic organs. It is also known that the pubococcygeus muscle (PcM) contracts in the storage phase and is inactive during voiding, while the bulbospongiosus muscle (BsM) is active during the voiding phase. Recent evidence suggested an additional role of these muscles in supporting urethral closure in rabbits. However, the individual role of perineal and pelvic muscles as urethral sphincters is not well-defined. Here we evaluated the individual, sequential and synergistic roles of the PcM and BsM in assisting urethral closure and defined the optimal electrical stimulation parameters that can effectively contract these muscles and increase the urethral pressure (P _ura ) in young nulliparous animals (n = 11). Unilateral stimulation of either the BsM or PcM at 40 Hz induced modest increases in average P _ura (0.23 ± 0.10 and 0.07 ± 0.04 mmHg, respectively). Investigation on the changes in P _ura evoked by stimulation frequencies between 5 and 60 Hz show that sequential contralateral PcM-BsM activation at 40 Hz induced a 2-fold average P _ura increase (0.23 ± 0.07 mmHg) compared to that evoked by PcM stimulation. Simultaneous activation of PcM and BsM at 40 Hz also showed an increased average P _ura (0.26 ± 0.04 mmHg), with a 2-fold increase in average P _ura observed during the unilateral sequential PcM-BsM stimulation at 40 Hz (0.69 ± 0.2 mmHg). Finally, stimulation at 40 Hz of the bulbospongiosus nerve (BsN) induced an approximate 4-fold increase in average P _ura (0.87 ± 0.44 mmHg; p < 0.04) compared to that elicited by BsM stimulation, confirming that direct nerve stimulation is more effective. Together, this study shows that in the female rabbit, both perineal and pelvic muscles support of the urethral function during continence, and that unilateral stimulation of the BsN at 40-60 Hz is sufficient to achieve maximal secondary sphincter activity. The results also support the potential clinical value of neuromodulation of pelvic and perineal nerves as bioelectronic therapy for stress urinary incontinence.

Usefulness of transperineal shear wave elastography of levator ani muscle in women with stress urinary incontinence

This study aimed to quantitatively assess the quality of levator ani muscle (LAM) using shear wave elastography (SWE) and to evaluate the association between the elasticity of LAM and stress urinary incontinence (SUI). The study population included 32 women with SUI and 34 women with normal pelvic support. The thickness of LAM, bladder neck descent (BND), and urethral funneling (UF) were assessed by transperineal ultrasound. LAM elasticity was measured by SWE at rest and during the maximal Valsalva maneuver. Age, menopause, BND, and UF showed a positive correlation with SUI. There was no significant between-group difference in the elastic modulus values of LAM at rest. The thickness of LAM in women with SUI was greater than that in control group at rest and during the maximal Valsalva maneuver (P < 0.001). The elastic modulus values of E_max and E_mean were significantly increased from rest to the maximal Valsalva maneuver in all participants (56.24 vs 82.43 kPa and 47.92 vs 72.37 kPa, P < 0.001). The change of these variables from rest to the maximal Valsalva maneuver in the control group was more obvious than that in the SUI group (34.09 vs 17.87 kPa and 31.55 vs 16.82 kPa, P < 0.05). The elasticity of LAM, as quantified by SWE, may potentially be used as an index for predicting SUI.

The Association of Hiatal Dimensions and Urethral Mobility With Stress Urinary Incontinence

OBJECTIVES

To investigate the association of hiatal area (HA), bladder neck mobility, and urethral mobility during the cough stress test (CST) with stress urinary incontinence (SUI).

METHODS

This was a prospective study of 110 continent and 190 incontinent women using transperineal ultrasound. HA, bladder neck mobility, and the mobility of six points along the urethra (Vectors 1-6) were measured. The cohort was randomly divided at a ratio of 2:1 into a training cohort and a validation cohort. The correlations of HA with bladder neck mobility, urethral mobility, and SUI were tested. The predictive model was yielded by fisher linear discriminant analysis and receiver operating characteristics to assess the parameters' ability to predict SUI.

RESULTS

Valid data were collected from 177 incontinent women and 105 continent women. Significant differences were identified in HA, body mass index (BMI), funneling, bladder neck mobility, and Vectors 1-6 between them. HA was positively correlated to bladder neck mobility. In the training cohort, bladder neck position on Valsalva, Vectors 3, and BMI had the area under curves of 0.74, 0.69, and 0.66 (all P < 0.001); Funneling and Vector 3 had odds ratios of 18.96 and 3.65 (all P < 0.001), for predicting SUI. The predictive model incorporating funneling, Vectors 3, and BMI provided the best performance in predicting SUI in both cohorts.

CONCLUSION

The larger the HA was, the higher the bladder neck mobility. However, it was mid-urethral mobility rather than bladder neck mobility that performed best at predicting SUI.

The correlation between transperineal ultrasound assessment of the levator ani muscle and postpartum urinary incontinence

AIMS

The primary aim of the present study was to assess the association between levator ani muscle (LAM) integrity and function on the one hand, and the risk of urinary incontinence (UI) on the other. A secondary objective was to assess the association between fundal pressure in the second stage of labor (Kristeller maneuver) and the risk of postpartum UI.

METHODS

In this prospective cohort study, women underwent a clinical and transperineal ultrasound examination at rest, at pelvic floor muscle contraction (PFMC), and at Valsalva maneuver 3-6 months after their first vaginal delivery. LAM avulsion and levator hiatal area (LHA) were evaluated. In addition, women were interviewed about the presence of UI, whether stress (SUI) or urgency (UUI).

RESULTS

Overall, data of 244 women were analyzed. SUI was reported in 50 (20.5%), while UUI was reported in 19 (7.8%) women. Women who reported SUI had a higher prevalence of LAM avulsion and less proportional reduction in LHA from rest to a maximum contraction in comparison to women with no SUI. Women who reported UUI had a greater LHA at rest, during contraction, and during maximal Valsalva in comparison to women without UUI. No significant association was found between the Kristeller maneuver and the incidence of any UI.

CONCLUSION

Levator ani avulsion and less proportional reduction of LHA with PFMC appear to be associated with a higher risk of postpartum urinary stress incontinence.

Pelvic floor dysfunction one year after first childbirth in relation to perineal tear severity

The aims of this study were to evaluate pelvic floor dysfunction symptoms one year after delivery and investigate whether adverse functional outcomes after childbirth were related to the degree of perineal injury. A prospective cohort of 776 primiparas were included. Self-reported pelvic floor function data were obtained using a web-based questionnaire. Women with no/first-degree injuries, second-degree injuries, third-/fourth-degree injuries (obstetric anal sphincter injury, OASI) and cesarean section were compared. A total of 511 women (66%) responded. Second-degree tears were a risk factor for stress incontinence (aOR 2.6 (95% CI 1.3–5.1)). Cesarean section was protective against stress incontinence (aOR 0.2 (95% CI 0.1–0.9)). OASI was a risk factor for urge incontinence (aOR 4.8 (95% CI 1.6–15)), prolapse (aOR 7.7 (95% CI 2.1–29)) and pelvic pain (OR 3.3 (95% CI 1.1–10)). Dyspareunia was reported by 38% of women, 63% of women in the OASI group (aOR 3.1 (95% CI 1.1–9.0)). Women with OASI reported that the injury affected daily life (OR 18 (95% CI 5.1–59)). Pelvic floor dysfunction is common after childbirth, even in women with moderate injury. Women with OASI had significantly higher risks of symptoms of prolapse, urge urinary incontinence, pain, dyspareunia and impacts on daily life.

Ultrasound imaging of maternal birth trauma

INTRODUCTION AND HYPOTHESIS

The term 'maternal birth trauma' has undergone substantial changes in meaning over the last 2 decades. Leaving aside psychological morbidity, somatic trauma is now understood to encompass not just episiotomy, perineal tears and obstetric anal sphincter injuries (OASI), but also trauma to the levator ani muscle. This review covers diagnosis of maternal birth trauma by translabial ultrasound imaging.

METHODS

Narrative review.

RESULTS

Tomographic imaging of pelvic structures with the help of 4D ultrasound, used since 2007, has allowed international standardization and seems to be highly reproducible and valid for the diagnosis of OASI and levator avulsion.

CONCLUSIONS

Translabial and exo-anal ultrasound allows the assessment of maternal birth trauma in routine clinical practice and the utilization of avulsion and sphincter trauma as key performance indicators of maternity services. It is hoped that this will lead to a greater awareness of maternal birth trauma among maternity caregivers and improved outcomes for patients, both in the short term and in the decades to come.

The effect of preoperative pelvic floor muscle training on urinary and colorectal-anal distress in women undergoing pelvic organ prolapse surgery-a randomized controlled trial

Introduction and hypothesis

Pelvic floor muscle training (PFMT) improves urinary incontinence and mild pelvic organ prolapse (POP). We aimed to investigate the effect of preoperative PFMT on urinary and colorectal-anal distress and related quality of life (QoL) in women with severe POP scheduled for surgery.

Methods

Randomized controlled trial of 159 women scheduled for POP surgery (intervention = 81, controls = 78). Intervention consisted of daily PFMT from inclusion to the day of surgery. Symptoms and QoL were assessed at inclusion, day of surgery and 6 months postoperatively using the Urinary Distress Inventory (UDI-6), Colorectal-Anal Distress Inventory (CRADI-8), Urinary Impact Questionnaire (UIQ) and Colorectal-Anal Impact Questionnaire (CRAIQ) (range 0–100). Mixed model statistical analyses were used.

Results

One hundred fifty-one (95%) women completed the study (intervention = 75, controls = 76). Mean waiting times until surgery and follow-up were 22 and 28 weeks. There was no difference in mean postoperative symptom and QoL scores (95% CI) between the intervention and control group: UDI-6 16 (12–21) vs. 17 (13–22), CRADI-8 15 (11–18) vs. 13 (10–16), UIQ 11 (7–15) vs. 10 (6–13) and CRAIQ 5 (2–7) vs. 6 (4–9), all p > 0.05. Overall mean scores were reduced from baseline to postoperative follow-up: UDI-6 37 (33–41) vs. 17 (14–20), CRADI-8 22 (19–25) vs. 14 (11–16); UIQ 28 (24–32) vs. 10 (7–13) and CRAIQ 16 (12–19) vs. 5 (3–7), all p < 0.01.

Conclusions

We found no added effect of preoperative PFMT on symptoms or QoL related to urinary and colorectal-anal distress in women scheduled for POP surgery. They achieved symptomatic improvement postoperatively regardless of PFMT.

Clinical trial registration

The study was registered in clinicaltrials.gov: NCT 03,064,750.

Association between levator ani avulsion and urinary incontinence in women: A systematic review and meta-analysis

Background

Urinary incontinence is a bothersome symptom. Although the relationship between stress urinary incontinence (SUI) and vaginal delivery is established, the pathology underlying SUI after vaginal birth remains to be elucidated.

Objectives

To determine whether levator ani muscle avulsion predisposes for SUI in women.

Search strategy

Pubmed and Embase were searched for terms and their variations “levator ani muscle avulsion” and “urinary incontinence”, from inception until 5 November 2019.

Selection criteria

Inclusion criterion: studies describing the relationship between urinary incontinence and levator ani muscle avulsion in women at least 1 year after delivery. Exclusion criterion: studies only analyzing the urethral sphincter or hiatus dimensions.

Data collection and analysis

Odds ratios were used and if not available, were calculated as means of data synthesis, adjusted odds ratios if presented by the study, random‐effects model to compute a pooled estimate.

Results

Seven studies were included, accounting for 2388 women. Comparing women with and without levator ani muscle avulsion, the overall odds ratio for SUI is 0.87 (95% confidence interval 0.56–1.34), and after adjustment for possible confounders was 0.72 (95% confidence interval 0.40–1.30).

Conclusion

There is no relationship between levator ani muscle avulsion and SUI in women.

A systematic review and meta‐analysis was conducted to evaluate the relationship between levator ani muscle avulsion and stress urinary incontinence, which could not be supported.

Association between elastography findings of the levator ani and stress urinary incontinence

PURPOSE

To investigate the elasticity of the levator ani musle (LAM) with the patients suffering from stress urinary incontinence (SUI) by transperineal elastography.

METHODS

Conventional transperineal ultrasound and elastography were performed in the patients with SUI on quiescent condition and maximal Valsalva. Transperineal ultrasound and elastography were repeated after Kegel exercises. The scoring system and strain ratio (SR) values were recorded and analyzed.

RESULTS

After Kegel exercises, the ratio of subjective improvement or cure was 81 % (102/126). Mean elasticity score (ES) and SR of LAM were significantly higher than the value before on maximal Valsalva, respectively. Mean ES and SR of LAM after Kegel exercises were similar with the value before on quiescent condition, respectively.

CONCLUSION

The improvement of SUI was associated with the stiffer LAM assessed by elastography. Women with SUI who have softer LAM were more likely to have symptoms of SUI and Kegel exercise could strengthen the stiffness of LAM.

BRIEF SUMMARY

The improvement of SUI was associated with the stiffer LAM assessed by elastography.

Impact of gestational diabetes on pelvic floor: A prospective cohort study with three-dimensional ultrasound during two-time points in pregnancy

AIM

To evaluate the pelvic floor (PF) biometry using three-dimensional ultrasound (US) at two-time points of gestational in pregnant women with gestational diabetes mellitus (GDM).

METHODS

A prospective cohort study conducted at the Perinatal Diabetes Research Center including 44 pregnant women with GDM and 66 pregnant women without GDM at 24 to 28 weeks of gestation. Three-dimensional transperineal US was performed at 24 to 28 and 34 to 38 weeks of gestation in the lithotomy position at rest. The axial plane of the minimal Levator hiatal dimensions was used to determine Levator ani muscle and Hiatal area (HA) biometry at 24 to 28 and 34 to 38 weeks of gestation.

RESULTS

Of the 110 pregnant women, 100 (90.9%) completed the follow-up at 34 to 38 weeks of gestation. The evaluation by US showed a negative biometric change between the two-time points, during pregnancy in women with GDM; in the HA (β coefficient: estimative of effect in biometric progression according to GDM diagnosis, using the non-GDM group as reference = -6.76; P = .020), anteroposterior diameter (β = -5.07; P = .019), and Levator ani thickness (β = -12.34; P = .005).

CONCLUSIONS

Pregnant women with GDM had a significantly lower than expected percentage of changes in biometry of Levator ani thickness and HA from 24 to 28 to 34 to 38 weeks of gestation when compared with the group of pregnant women without GDM. GDM alters the morphology of PF structures assessed by three-dimension US. This reported complication may be implicated in adverse birth outcomes and may play a role in the development of PF dysfunction.