Association of levator injury and urogynecological complaints in women after their first vaginal birth with and without mediolateral episiotomy

Pelvic floor dysfunction after intervention, compared with expectant management, in prolonged second stage of labour: A population-based questionnaire and cohort study

OBJECTIVE

To investigate the effect of vacuum extraction (VE) or caesarean section (CS), compared with expectant management, on pelvic floor dysfunction (PFD) 1-2 years postpartum in primiparous women with a prolonged second stage of labour.

DESIGN

A population-based questionnaire and cohort study.

SETTING

Stockholm, Sweden.

POPULATION

A cohort of 1302 primiparous women with a second stage duration of ≥3 h, delivering from December 2017 to November 2018.

METHODS

The 1-year follow-up questionnaire from the Swedish National Perineal Laceration Register was distributed 12-24 months postpartum. Exposure was VE or CS at 3-4 h or 4-5 h, compared with expectant management.

MAIN OUTCOME MEASURES

Pelvic floor dysfunction was defined as at least weekly symptoms of urinary incontinence, pelvic organ prolapse or a Wexner score of ≥4. The risk of PFD was calculated using Poisson regression with robust variance estimation, presented as crude and adjusted relative risks (RRs and aRRs) with 95% confidence intervals (95% CIs). The implication of obstetric anal sphincter injury (OASI) on pelvic floor disorders was investigated through mediation analysis.

RESULTS

In total, 35.1% of women reported PFD. Compared with expectant management, the risk of PFD was increased after VE at 3-4 h (aRR 1.33, 95% CI 1.06-1.65) and 4-5 h (aRR 1.34, 95% CI 1.05-1.70), but remained unchanged after CS. The increased risk after VE was not mediated by OASI.

CONCLUSIONS

Pelvic floor dysfunction was common in primiparous women after a prolonged second stage, and the risk of PFD increased after VE but was unaffected by CS, compared with expectant management. If a spontaneous vaginal delivery eventually occurred, allowing an extended duration of labour did not increase the risk of PFD.

A model to predict delivery time following induction of labor at term with a dinoprostone vaginal insert: a retrospective study

BACKGROUND

Dinoprostone vaginal insert is the most common pharmacological method for induction of labor (IOL); however, studies on assessing the time to vaginal delivery (DT) following dinoprostone administration are limited.

AIMS

We sought to identify the primary factors influencing DT in women from central China, at or beyond term, who underwent IOL with dinoprostone vaginal inserts.

METHODS

In this retrospective observational study, we analyzed the data of 1562 women at 37 weeks 0 days to 41 weeks 6 days of gestation who underwent dinoprostone-induced labor between January 1st, 2019, and December 31st, 2021. The outcomes of interest were vaginal or cesarean delivery and factors influencing DT, including maternal complications and neonatal characteristics.

RESULTS

Among the enrolled women, 71% (1109/1562) delivered vaginally, with median DT of 740.50 min (interquartile range 443.25 to 1264.50 min). Of the remaining 29% (453/1562), who delivered by cesarean section, 11.9% (54/453) were multiparous. Multiple linear regression analysis showed that multiparity, advanced maternal age, fetal macrosomia, premature rupture of membranes (PROM), and daytime insertion of dinoprostone were the factors that significantly influenced DT. Time to vaginal delivery increased with advanced maternal age and fetal macrosomia and decreased with multiparity, PROM, and daytime insertion of dinoprostone. A mathematical model was developed to integrate these factors for predicting DT: Y = 804.478 - 125.284 × multiparity + 765.637 × advanced maternal age + 411.511 × fetal macrosomia-593.358 × daytime insertion of dinoprostone - 125.284 × PROM.

CONCLUSIONS

Our findings may help obstetricians estimate the DT before placing a dinoprostone insert, which may improve patient management in busy maternity wards and minimize potential risks.

Systematic Review and Meta-analysis of the Prevalence of Levator Ani Avulsion with Obstetric Anal Sphincter Injury and its Effects on Pelvic Floor Dysfunction

INTRODUCTION AND HYPOTHESIS

The objective was to evaluate the prevalence of levator ani avulsion (LAA) among primiparous women with obstetric anal sphincter injury (OASI) and how this association could affect future pelvic floor dysfunction.

METHODS

Three electronic databases (MEDLINE/PubMed/EMBASE) were searched in December 2018 and again in October 2022. Nine full-text articles were included in the analysis. The exclusion criteria were language other than English, studies not based on primiparous women only, conference abstracts, and evaluation without ultrasound or MRI.

RESULTS

The overall prevalence of LAA was 24% (95% CI: 18-30%). Those with OASI, were at a higher risk of LAA, OR 3.49 (95% CI: 1.46 to 8.35). In women with LAA + OASI versus OASI alone, Three of Five studies showed worsened AI symptoms. Three of Five studies assessing urinary incontinence (UI) reported no significant difference in UI, whereas two reported increased UI. All studies that looked at pelvic organ prolapse reported a higher incidence of symptomatic prolapse and reduced pelvic floor muscle strength in women with LAA + OASI compared with those without LAA.

CONCLUSION

Levator ani avulsion is prevalent following vaginal birth and is strongly associated with OASI. Incidence of AI does not increase in women with LAA and OASI, but they had greater symptom bother. OASI with LAA appears to increase the incidence of pelvic floor weakness and pelvic organ prolapse. There is no consensus agreement on the effect of LAA + OASI on UI.

Impact of the Duration of the Second Stage of Labor on Postpartum Pelvic Floor Symptoms

IMPORTANCE

The associated effect of duration of the second stage of labor (SSL) on pelvic floor symptoms development is not well studied.

OBJECTIVE

This study aimed to examine the association between duration of SSL and pelvic floor symptoms at 6 months postpartum among primiparous women.

STUDY DESIGN

A planned secondary analysis of a multicenter randomized trial evaluating the impact of immediate versus delayed pushing on vaginal delivery rates, maternal morbidity, and neonatal outcomes was conducted between 2014 and 2018. For pelvic floor arm participants, demographic, pelvic examination, and validated questionnaire data were collected postpartum. Primary outcome was change in Pelvic Floor Distress Inventory 20 (PFDI-20) score from immediate to 6 months postpartum. Secondary outcomes included changes in the Pelvic Floor Impact Questionnaire, Fecal Incontinence Severity Index, Modified Manchester Health Questionnaire scores, and Pelvic Organ Prolapse Quantification measurements at 6 months postpartum. Participants were analyzed by SSL duration ≤60 minutes or >60 minutes.

RESULTS

Of the 2,414 trial participants, 767 (32%) completed pelvic floor assessments at 6 months. Pelvic Floor Distress Inventory 20 scores significantly improved at 6 months in the ≤60 minutes SSL group compared with >60 minutes SSL (-14.3 ± 48.0 and -3.2 ± 45.3, respectively; P = 0.04). Changes from immediate postpartum in total and subscale scores for other questionnaires at 6 months did not differ between groups. Prolapse stage did not differ between groups. Perineal body was significantly shorter in the >60 minutes SSL group (3.7 ± 0.7, 3.5 ± 0.8; P = 0.03).

CONCLUSIONS

Women with SSL >60 minutes experience less improvement in PFDI-20 scores at 6 months. Greater tissue and innervation trauma in those with SSL >60 minutes may explain persistently less improvement in PFDI-20 scores.

Episiotomy in vacuum extraction, do we cut the levator ani muscle? A prospective cohort study

INTRODUCTION AND HYPOTHESIS

Vaginal delivery may lead to levator ani muscle (LAM) injury or avulsion. Episiotomy may reduce obstetric anal sphincter injury in operative vaginal delivery, but may increase the risk of LAM injury. Our aim was to assess whether lateral episiotomy in vacuum extraction (VE) in primiparous women causes LAM injury.

METHODS

A prospective cohort study of 58 primiparous women with episiotomy nested within an ongoing multicenter randomized controlled trial of lateral episiotomy versus no episiotomy in VE (EVA trial) was carried out in Sweden. LAM injury was evaluated using 3D endovaginal ultrasound 6-12 months after delivery and Levator Ani Deficiency (LAD) score. Episiotomy scar properties were measured. Characteristics were described and compared using Chi-squared tests. We stipulated that if a lateral episiotomy cuts the LAM, ≥50% would have a LAM injury. Among those, ≥50% would be side specific. We compared the observed prevalence with a test of one proportion.

RESULTS

Twelve (20.7%, 95% CI 10.9-32.9) of 58 women had a LAD (p < 0.001, compared with the stipulated 50%). Six (50.0%, 95% CI 21.1% to 78.9%) of 12 women had a LAD on the episiotomy side, including those with bilateral LAD (p = 1.00). Two (16.7%, 95% CI 2.1% to 48.4%) of 12 women had a LAD exclusively on the episiotomy side (p = 0.02).

CONCLUSIONS

There was no excessive risk of cutting the LAM while performing a lateral episiotomy. LAD was not seen in women with episiotomies shorter than 18 mm.

Two year follow-up and comparison of pelvic floor muscle electromyography after first vaginal delivery with and without episiotomy and its correlation with urinary incontinence: A prospective cohort study

INTRODUCTION

Few prospective studies have revealed the long-term neuromuscular alterations of pelvic floor after vaginal delivery. The aim of this study was to evaluate the impact of episiotomy on the electrical activity of pelvic floor muscle 2 years following vaginal delivery, and explore the relation between surface electromyography (sEMG) amplitudes and urinary incontinence.

MATERIAL AND METHODS

A total of 427 primiparous women with full-term singleton vaginal delivery were included in the cohort and 362 with no further births within the 2 year follow-up completed observations. Of these, 200 underwent episiotomy and 162 underwent nonepisiotomy. Clinical demographic characteristics, vaginal EMG variables and urinary incontinence-specific questionnaire scores were collected at 6 weeks, 6, 12 and 24 months after childbirth, respectively. Primary outcomes were the comparison of sEMG values between the episiotomy and nonepisiotomy groups throughout 2 years. Secondary outcomes were the correlation between sEMG of both groups and the incidence and severity of urinary incontinence. Spearman's correlation analysis, Kruskal-Wallis test and ANOVA with Bonferroni correction were used to analyze the variables.

RESULTS

Amplitude of maximal fast and endurance contractions on sEMG in the episiotomy group was significantly lower than the nonepisiotomy counterpart. Such difference of sEMG persisted for a long period after birth: endurance contraction, 33.12 ± 8.92 vs 35.085 ± 9.98, p < 0.01 at 24 months, and fast contraction, 36.53 ± 8.87 vs 39.05 ± 9.98, p = 0.01 at 12-month. Although there was no significant difference in incidence and severity of urinary incontinence between both groups, a negative correlation existed between EMG values of muscle contraction and urinary incontinence symptoms throughout.

CONCLUSIONS

Primiparous women delivered with episiotomy demonstrated lower contractile sEMG activity of pelvic floor muscle in the long term. The lower sEMG values of fast contraction were associated with urinary incontinence symptoms.

Which factors are associated with anal incontinence after obstetric anal sphincter injury?

OBJECTIVES

Obstetric anal sphincter injury (OASI) is an important factor in the etiology of anal incontinence. This study aimed to evaluate whether anal sphincter defects, levator avulsion or levator ballooning after OASI are associated with severity of anal incontinence. Furthermore, we evaluated whether factors such as constipation and altered stool consistency are associated with symptoms of incontinence after OASI.

METHODS

In this multicenter prospective observational cohort study, women with OASI were invited to participate at least 3 months after primary repair. All women completed validated questionnaires, including St Mark's incontinence score, Bristol stool scale (BSS) and Cleveland clinic constipation score (CCCS), and underwent four-dimensional (4D) transperineal ultrasound for assessment of the levator ani muscle and anal sphincter.

RESULTS

In total, 220 women were included. Median follow-up was 4 months (range, 3-98 months). Univariate linear regression analysis showed an association of St Mark's incontinence score with a residual defect of the external anal sphincter (EAS) (β, 1.55 (95% CI, 0.04-3.07); P = 0.045), higher parity (β, 0.85 (95% CI, 0.02-1.67); P = 0.046), BSS (β, 1.28 (95% CI, 0.67-1.89); P < 0.001) and CCCS (β, 0.36 (95% CI, 0.18-0.54); P < 0.001). However, multivariate linear regression found an association of St Mark's incontinence score only with BSS (β, 1.50 (95% CI, 0.90-2.11); P < 0.001) and CCCS (β, 0.46 (95% CI, 0.29-0.63); P < 0.001).

CONCLUSIONS

Residual defects of the EAS, detected on 4D transperineal ultrasound, are associated with severity of anal incontinence symptoms measured using St Mark's incontinence score 4 months after OASI repair. Furthermore, clinical factors such as constipation and altered stool consistency appear to influence this association and may therefore play a more important role in clinical management. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Levator ani avulsion: a Systematic evidence review (LASER)

BACKGROUND

There is variation in the reported incidence rates of levator avulsion (LA) and paucity of research into its risk factors.

OBJECTIVE

To explore the incidence rate of LA by mode of birth, imaging modality, timing of diagnosis and laterality of avulsion.

SEARCH STRATEGY

We searched MEDLINE, EMBASE, CINAHL, AMED and MIDIRS with no language restriction from inception to April 2019.

STUDY ELIGIBILITY CRITERIA

A study was included if LA was assessed by an imaging modality after the first vaginal birth or caesarean section. Case series and reports were not included.

DATA COLLECTION AND ANALYSIS

RevMan v5.3 was used for the meta-analyses and SW SAS and STATISTICA packages were used for type and timing of imaging analyses.

RESULTS

We included 37 primary non-randomised studies from 17 countries and involving 5594 women. Incidence rates of LA were 1, 15, 21, 38.5 and 52% following caesarean, spontaneous, vacuum, spatula and forceps births, respectively, with no differences by imaging modality. Odds ratio of LA following spontaneous birth versus caesarean section was 10.69. The odds ratios for LA following vacuum and forceps compared with spontaneous birth were 1.66 and 6.32, respectively. LA was more likely to occur unilaterally than bilaterally following spontaneous (P < 0.0001) and vacuum-assisted (P = 0.0103) births but not forceps. Incidence was higher if assessment was performed in the first 4 weeks postpartum.

CONCLUSIONS

LA incidence rates following caesarean, spontaneous, vacuum and forceps deliveries were 1, 15, 21 and 52%, respectively. Ultrasound and magnetic resonance imaging were comparable tools for LA diagnosis.

TWEETABLE ABSTRACT

Levator avulsion incidence rates after caesarean, spontaneous, vacuum and forceps deliveries were 1, 15, 21 and 52%, respectively.

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.

Prevalence of levator ani avulsion in a multicenter study (PAMELA study)

PURPOSE

The objective is to determine the prevalence of levator ani muscle (LAM) avulsion using four-dimensional ultrasound in primiparous women after vaginal delivery and according to delivery mode.

METHODS

This prospective, multicenter study included 322 women evaluated at 6-12 months postpartum by four-dimensional transperineal ultrasound to identify levator ani muscle avulsion. The researcher who performed the ultrasound was blinded to all clinical data. Meaningful data about the birth were also recorded: mode of delivery, mother's age and body mass index, duration of second stage, episiotomy, perineal tearing, anesthesia, assistant, head circumference and fetal weight.

RESULTS

303 volumes were valid for evaluation. The overall prevalence of levator ani muscle avulsion was 18.8% (95% CI 14.4-23.2%). In our multivariate analysis, only mode of delivery reached statistical significance as a risk factor for levator ani muscle avulsion (p < 0.001). The prevalence according to the different modes of delivery was 7.8% in spontaneous delivery, 28.8% in vacuum-assisted and 51.1% in forceps-assisted delivery. Compared with spontaneous delivery, the OR for LAM avulsion was 12.31 with forceps (CI 95% 5.65-26.80) and 4.78 with vacuum-assisted delivery (CI 95% 2.15-10.63).

CONCLUSIONS

Levator ani avulsion during vaginal delivery in primiparous women occurs in nearly one in every five deliveries. Delivery mode is a significant and modifiable intrapartum risk factor for this lesion. The incidence is lower in spontaneous delivery and significantly increases when an instrument is used to assist delivery, especially forceps.

New concepts in regenerative medicine approaches to the treatment of female stress urinary incontinence

PURPOSE OF REVIEW

Update on recent regenerative medicine approaches to the treatment of stress urinary incontinence (SUI) caused by intrinsic sphincter deficiency (ISD).

RECENT FINDINGS

In the treatment of female SUI/ISD, results using different types of cellular therapy have been disappointing, and new approaches are desirable. To advance our regenerative medicine approaches to SUI/ISD, it is critical to utilize animal models that best parallel the pathophysiology of this disease in women. Many current animal models mimic acute SUI/ISD. However, SUI/ISD in women is usually a chronic condition resulting from previous muscle and nerve sphincter damage during parturition or muscle loss during aging. Similar to women, a nonhuman primate (NHP) model of chronic SUI/ISD has demonstrated only modest response to cell therapy. However, treatment with stromal cell-derived factor 1 (SDF1), also known as C-X-C motif chemokine 12 (CXCL12) restored continence in this model.

SUMMARY

As a potential therapeutic approach, the use of a well characterized chemokine, such as CXCL12, may by-pass the lengthy and expensive process of cell isolation, expansion, and injection. Recent findings in this new NHP model of chronic SUI/ISD may open up the field for noncell-based treatments.

Postpartum sexual function; the importance of the levator ani muscle

Introduction and hypothesis

Pelvic floor muscle function plays an important role in female sexual functioning. Smaller genital hiatal dimensions have been associated with sexual dysfunction, mainly dyspareunia. On the other hand, trauma of the levator ani muscle sustained during childbirth is associated with increased genital hiatus, which potentially can affect sexual functioning by causing vaginal laxity. This study aims to determine the association between levator hiatal dimensions and female sexual dysfunction after first vaginal delivery.

Methods

This is a secondary analysis of a prospective observational study. Two hundred four women who had a first, spontaneous vaginal delivery at term between 2012 and 2015 were recruited at a minimum of 6 months postpartum. Thirteen pregnant women were excluded. We analyzed the association of total PISQ-12 score, as well as individual sexual complaints (desire, arousal, orgasm and dyspareunia), with levator hiatal dimensions at rest, with maximum Valsalva and during pelvic floor muscle contraction as measured by 4D transperineal ultrasound. Statistical analysis was performed using linear regression analysis and Mann-Whitney U test.

Results

One hundred ninety-one women were evaluated at a median of 11 months postpartum. There was no significant association between total PISQ-12 score and levator hiatal dimensions. Looking at individual sexual complaints, women with dyspareunia had significantly smaller levator hiatal area and anterior-posterior diameter on maximum Valsalva. By using multivariate logistic regression analysis however we found dyspareunia was not independently associated with levator hiatal dimensions.

Conclusions

After first vaginal delivery sexual dysfunction is not associated with levator hiatal dimensions as measured by 4D transperineal ultrasound.

Pelvic floor disorders following different delivery modes-a population-based cohort analysis

INTRODUCTION AND HYPOTHESIS

Identifying protective factors against pelvic floor disorders (PFDs) is important. We investigated whether cesarean delivery (CD) at the indication of abnormal second stage of labor (ASSL) has the same protective effect against future PFDs.

METHODS

This population-based cohort study included deliveries occurring from 1991-2017 in a tertiary medical center. Women were grouped by their delivery mode: patients with vaginal deliveries (VD) only; those with CD only, excluding second-stage indications; and those with CD due to ASSL. The outcome measure, PFDs and related repair diagnoses, included any recorded hospitalization involving a pre-defined set of ICD-9 codes. A Kaplan-Meier survival curve compared cumulative PFD morbidity in the different groups, and a Cox proportional hazards model controlled for confounders.

RESULTS

A total of 106,003 patients met the inclusion criteria; 86.7% (n = 91,856) experienced VD only, 11.7% (n = 12,359) underwent CD only and 1.7% (n = 1788) had at least one CD due to ASSL. PFD-related hospitalization incidence was 0.7% (n = 719) for the entire cohort. While a significantly higher PFD-related hospitalization rate was recorded in the VD group (0.7%) compared with the ASSL CD group (0.3%) and the non-ASSL CD group (0.5%, p < 0.001), after controlling for potential confounders, an independent and protective association was noted between CD and later PFDs only in parturients who did not experience ASSL (aHR 0.679, 95% CI 0.51-0.90, p = 0.006).

CONCLUSIONS

CDs may be protective against later PFD development only if performed prior to the second stage of labor.