Prevalence of levator ani muscle injury and health-related quality of life in primiparous Chinese women after instrumental delivery

Association of pre-pregnancy body mass index and gestational weight gain on postpartum pelvic floor muscle morphology and function in Chinese primiparous women: A retrospective cohort study

OBJECTIVE

Our study aimed to investigate the association between maternal pre-pregnancy body mass index (BMI), gestational weight gain (GWG), and impaired pelvic floor muscle (PFM) morphology and function during the early postpartum period.

METHODS

This retrospective cohort study was conducted at Shanghai First Maternity and Infant Hospital from December 2020 to December 2022. A total of 1118 primiparous women with singleton pregnancies who underwent vaginal deliveries and participated in postpartum PFM assessments were included. Maternal pre-pregnancy BMI and GWG were considered as exposures. PFM morphology and function impairment were the primary outcomes. PFM morphology impairment, defined as levator ani muscle avulsion, was assessed using transperineal ultrasound. PFM function impairment, manifested as diminished PFM fiber strength, was assessed through vaginal manometry. Multivariable logistic regression analysis was employed to calculate adjusted odds ratios (aOR) with 95% confidence intervals (CI). Restricted cubic spline models were used to validate and visualize the relationship.

RESULTS

Women with lower pre-pregnancy BMI were at an increased risk of levator ani muscle avulsion (aOR = 1.73, 95% CI: 1.10-2.70, P = 0.017), particularly when combined with excessive GWG during pregnancy (aOR = 3.20, 95% CI: 1.15-8.97, P = 0.027). Lower pre-pregnancy BMI was also identified as an independent predictor of PFM weakness (aOR = 1.53, 95% CI: 1.08-2.16, P = 0.017 for type I fiber injuries). Notably, regardless of the avulsion status, both underweight and overweight/obese women faced an elevated risk of reduced PFM strength (aOR = 1.74, 95% CI: 1.17-2.59, P = 0.006 for underweight women with type I fiber injuries; aOR = 1.67, 95% CI: 1.06-2.64, P = 0.027; and aOR = 1.73, 95% CI: 1.09-2.76, P = 0.021 for overweight/obese women with type I and type II fibers injuries, respectively).

CONCLUSIONS

Both lower and higher pre-pregnancy BMI, as well as excessive GWG, were strongly associated with PFM impairments. These findings highlighted the critical importance of comprehensive weight management throughout pregnancy to effectively promote women's pelvic health.

Obstetric risk factors for levator ani muscle avulsion: A systematic review and meta-analysis

OBJECTIVES

Women have a 11% lifetime risk of undergoing surgery for vaginal prolapse. Levator ani muscle (LAM) avulsion is one etiological factor associated with primary and recurrent pelvic organ prolapse. Pelvic organ prolapse has been shown to greatly affect the quality of life and well-being of women. Conduct a meta-analysis identifying risk factors associated with LAM avulsion recognised on transperineal ultrasound (TPUS) or magnetic resonance imaging (MRI) in primiparous women after vaginal birth.

STUDY DESIGN

OVID Medline, Embase and the Cochrane Library from inception to January 2021 were searched. Review Manager 5.3 (The Cochrane Collaboration) was used to analyse data. Odds ratios (OR) with 95% confidence intervals (95% CIs) were calculated. The heterogeneity among studies was calculated using the I2statistic.

RESULTS

Twenty-five studies were eligible for inclusion (n = 9333 women). Major LAM avulsion was diagnosed in an average of 22 % (range 12.7-39.5 %) of cases. Twenty-two studies used TPUS and three used MRI to diagnose avulsion. Modifiable and non-modifiable risk factors were identified. Significant predictors identified were forceps (OR 6.25 [4.33 - 9.0]), obstetric anal sphincter injuries (OR 3.93 [2.85-5.42]), vacuum (OR 2.41 [1.40-4.16]), and maternal age (OR 1.06 [1.02-1.10]).

CONCLUSIONS

This is the first meta-analysis of both modifiable and non-modifiable risk factors associated with LAM avulsion. This information could be used to develop a clinically applicable risk prediction model to target postnatal women at risk of LAM avulsion with a view to prevent the onset of pelvic floor organ prolapse.

The use of bubble charts in analyzing second stage cesarean delivery rates

BACKGROUND

The incidence of second stage cesarean delivery has been rising globally because of the failure or the anticipated difficulty of performing instrumental delivery. Yet, the best way to interpret the figure and its optimal rate remain to be determined. This is because it is strongly influenced by the practice of other 2 modes of birth, namely cesarean delivery performed before reaching the second stage and assisted vaginal birth during the second stage. In this regard, a bubble chart that can display 3-dimensional data through its x-axis, y-axis, and the size of each plot (presented as a bubble) may be a suitable method to evaluate the relationship between the rates of these 3 modes of births.

OBJECTIVE

This study aimed to conduct an epidemiologic study on the incidence of second stage cesarean deliveries rates among >300,000 singleton term births in 10 years from 8 obstetrical units and to compare their second stage cesarean delivery rates in relation to their pre-second stage cesarean delivery rates and assisted vaginal birth rates using a bubble chart.

STUDY DESIGN

The territory-wide birth data collected between 2009 and 2018 from all 8 public obstetrical units (labelled as A to H) were reviewed. The inclusion criteria were all singleton pregnancies with cephalic presentation that were delivered at term (≥37 weeks' gestation). Pre-second stage cesarean delivery rate was defined as all elective cesarean deliveries and those emergency cesarean deliveries that occurred before full cervical dilatation was achieved as a proportion of the total number of births. The second stage cesarean delivery rate and assisted vaginal birth rate were calculated according to the respective mode of delivery as a proportion of the number of cases that reached full cervical dilatation. The rates of these 3 modes of births were compared among the parity groups and among the 8 units. Using a bubble chart, each unit's second stage cesarean delivery rate (y-axis) was plotted against its pre-second stage cesarean delivery rate (x-axis) as a bubble. Each unit's second stage cesarean delivery to assisted vaginal birth ratio was represented by the size of the bubble.

RESULTS

During the study period, a total of 353,434 singleton cephalic presenting term pregnancies were delivered in the 8 units, and 180,496 (51.1%) were from nulliparous mothers. When compared with the multiparous group, the nulliparous group had a significantly lower pre-second stage cesarean delivery rate (18.58% vs 21.26%; P<.001) but a higher second stage cesarean delivery rate (0.79% vs 0.22%; P<.001) and a higher assisted vaginal birth rate (17.61% vs 3.58%; P<.001). Using the bubble of their averages as a reference point in the bubble chart, the 8 units' bubbles were clustered into 5 regions indicating their differences in practice: unit B and unit H were close to the average in the center. Unit A and unit F were at the upper right corner with a higher pre-second stage cesarean delivery rate and second stage cesarean delivery rate. Unit D and unit E were at the opposite end. Unit C was at the upper left corner with a low pre-second stage cesarean delivery rate but a high second stage cesarean delivery rate, whereas unit G was at the opposite end. Unit C and unit G were also in the extremes in terms of pre-second stage cesarean delivery to assisted vaginal birth ratio (0.09 and 0.01, respectively). Although some units seemed to have very similar second stage cesarean delivery rates, their obstetrical practices were differentiated by the bubble chart.

CONCLUSION

The second stage cesarean delivery rate must be evaluated in the context of the rates of pre-second stage cesarean delivery and assisted vaginal birth. A bubble chart is a useful method for analyzing the relationship among these 3 variables to differentiate the obstetrical practice between different units.

The use of bubble charts in analyzing the global second-stage cesarean delivery rates: a systematic review

OBJECTIVE

This study aimed to systematically review the worldwide second-stage cesarean delivery rate concerning pre-second-stage cesarean delivery and assisted vaginal birth rates.

DATA SOURCES

PubMed, Medline Ovid, EBSCOhost, Embase, Scopus, and Google Scholar were queried from inception to February 2023, with the following terms: "full dilatation," "second stage," and "cesarean," with their word variations. Furthermore, an additional cohort of 353,434 cases from our recently published study was included.

STUDY ELIGIBILITY CRITERIA

Only original studies that provided sufficient information on the number of pre-second-stage cesarean deliveries, second-stage cesarean deliveries, and vaginal births were included for the calculation of different modes of delivery. Systemic reviews, meta-analyses, or case reports were excluded.

METHODS

Study identification and data extraction were independently performed by 2 authors. Selected studies were categorized on the basis of parity, study period, and geographic regions for comparison.

RESULTS

A total of 25 studies were included. The overall pre-second-stage cesarean delivery rate, the second-stage cesarean delivery rate, and the second-stage cesarean delivery-to-assisted vaginal birth ratio were 17.94%, 2.65%, and 0.19, respectively. Only 5 studies described singleton, term, cephalic presenting pregnancies of nulliparous women, and their second-stage cesarean delivery rates were significantly higher than those studies with cohorts of all parity groups (4.50% vs 0.83%; P<.05). In addition, the second-stage cesarean delivery rate showed a secular increase across 2009 (0.70% vs 1.05%; P<.05). Moreover, it was the highest among African studies (5.14%) but the lowest among studies from East Asia and South Asia (0.94%). The distributions of second-stage cesarean delivery rates of individual studies and subgroups were shown with that of pre-second-stage cesarean delivery and assisted vaginal birth using the bubble chart.

CONCLUSION

The overall worldwide pre-second-stage cesarean delivery rate was 17.94%, the second-stage cesarean delivery rate was 2.65%, and the second-stage cesarean delivery-to-assisted vaginal birth ratio was 0.19. The African studies had the highest second-stage cesarean delivery rate (5.14%) and second-stage cesarean delivery-to-assisted vaginal birth ratio (1.88), whereas the studies from East Asia and South Asia were opposite (0.94% and 0.11, respectively).

Influence of Different Obstetric Factors on Early Postpartum Pelvic Floor Function in Primiparas After Vaginal Delivery

Purpose

This study sought to explore the obstetric factors affecting early postpartum pelvic floor function of primiparas after vaginal delivery.

Patients and Methods

We included 3362 primiparas who underwent postpartum re-examination in International Peace Maternity and Child Health Hospital at 42-60 days after delivery. The Glazer Protocol was used to evaluate their pelvic floor function, and univariate and multivariate logistic regression analyses were performed to identify obstetric factors that might affect it.

Results

Forceps-assisted delivery significantly increased the risk of the decline in fast- and slow-twitch muscle strength in the early postpartum period when compared with natural vaginal delivery (P < 0.05). Women with a pre-pregnancy body mass index (BMI) of ≥18.5 kg/m² had a decreased risk of decline in fast-twitch muscle strength than those with a pre-pregnancy BMI of <18.5 kg/m² (P < 0.05). Women who had a pre-pregnancy BMI of 24.0 to <28.0 kg/m² bore a decreased risk of decline in slow-twitch muscle strength than those with a pre-pregnancy BMI of <18.5 kg/m² (P < 0.05). The risk of decline in fast-twitch muscle strength and slow-twitch muscle in women with anemia during pregnancy was significantly increased (P < 0.05); women with second-stage labors of >2 h had an increased risk of fast-twitch and slow-twitch muscle strength decline than those with <2 h (P < 0.05).

Conclusion

Both pre-pregnancy underweight and obesity may cause impairment of early postpartum pelvic floor function. Forceps delivery, anemia during pregnancy, and the length of second stage of labor are independent factors leading to pelvic floor function impairment.

In vivo evaluation of the levator ani muscle in primiparous women using diffusion tensor imaging and fiber tractography

OBJECTIVE

To characterize the levator ani muscle (LAM) injury after first vaginal delivery and investigate the clinical application of diffusion tensor imaging (DTI) and fiber tractography in evaluating the LAM.

METHODS

Fifty-eight primiparous women at 6 weeks after vaginal delivery and 27 nulliparous women as controls underwent T2-weighted sequence and DTI sequence of the pelvic floor. A LAM scoring system was used to characterize the morphological changes. Fiber tractography of each major subdivision of LAM was performed, followed by assessment of the quality of fiber tracking. Fractional anisotropy (FA), apparent diffusion coefficient (ADC), fiber volume, and length were calculated.

RESULTS

Puborectalis and iliococcygeus injuries were observed in 30/58 (51.7%) and 10/58 (17.2%) primiparae, respectively. No LAM defects were identified in the control group. For the puborectalis, the FA values were lower (P = 0.010) and ADC values were higher (P = 0.024) in the primiparous group than in the control group. For the iliococcygeus, the fiber volume values were lower in the primiparous group than in the control group (P = 0.004).

CONCLUSION

Vaginal delivery can result in LAM injury at the puborectalis. DTI parameters can assist in the quantitative diagnosis of the LAM injury.

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.

Women with advanced pelvic organ prolapse and levator ani muscle avulsion would significantly benefit from mesh repair surgery

OBJECTIVES

Mesh repair surgery for pelvic organ prolapse (POP) has been suspended in some countries owing to concerns about its associated complications. However, mesh repair has been shown to reduce the risk of prolapse recurrence after surgery. In view of this controversy, our aim was to assess the incidence of subjective and objective recurrence of POP following mesh repair surgery vs native-tissue repair in women with Stage-III or Stage-IV POP.

METHODS

This was a prospective observational study of women who presented with Stage-III or Stage-IV POP and received primary prolapse surgery between 2013 and 2018. Transperineal ultrasound was performed before the operation and volumes were analyzed offline to assess the presence of levator ani muscle (LAM) avulsion. All women were counseled on either mesh repair or native-tissue reconstruction. The mesh-repair group was followed up for up to 5 years and the native-tissue-repair group for up to 2 years after the operation. Prolapse symptoms and POP quantification (POP-Q) staging were assessed at follow-up. Subjective recurrence of POP was defined as symptoms of prolapse (vaginal bulge sensation or dragging sensation) reported by the patient. Objective recurrence was defined as POP-Q ≥ Stage II. The subjective and objective recurrences of prolapse were compared between women with and those without mesh use. Multivariate regression analysis was used to identify risk factors for the recurrence of POP.

RESULTS

A total of 154 Chinese women with Stage-III or Stage-IV prolapse were recruited. Of these, 104 (67.5%) underwent mesh repair (transabdominal in 57 women and transvaginal in 47 women) and 50 (32.5%) had native-tissue repair surgery. Ninety-five (61.7%) women had LAM avulsion. Both the subjective POP recurrence rate (4.8% vs 20.0%; P = 0.003) and the objective recurrence rate (20.2% vs 46.0%; P = 0.001) were significantly lower in the mesh-repair group than in the native-tissue-repair group. On multivariate logistic regression analysis, mesh repair was associated significantly with a reduced risk of subjective recurrence (odds ratio (OR), 0.20 (95% CI, 0.07-0.63)) and of objective recurrence (OR, 0.16 (95% CI, 0.07-0.55)) of prolapse. On subgroup analysis of women with LAM avulsion, mesh repair significantly reduced the risk of subjective recurrence (OR, 0.24 (95% CI, 0.07-0.87)) and objective recurrence (OR, 0.23 (95% CI, 0.09-0.57)) of POP. The incidence of mesh-related complications was low, and mesh exposure could be treated conservatively or by minor surgery.

CONCLUSIONS

Mesh repair surgery, compared with native-tissue repair, was associated with a 5-fold reduction in the risk of subjective recurrence and a 6-fold reduction in the risk of objective recurrence of prolapse in women with Stage-III or Stage-IV POP. In women with concomitant LAM avulsion, mesh repair surgery was associated with a 4-fold reduction in both objective and subjective recurrence of POP. The rate of mesh-related complications was low, and mesh exposure could be treated conservatively or by minor surgery. The benefit of mesh surgery for these high-risk women appears to outweigh the risks of mesh complications, and it could be a treatment option for this group of women. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

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.

Malmström vacuum or Kielland forceps: which causes more damage to pelvic floor?

OBJECTIVE

To determine whether differences exist in the rate of levator ani muscle (LAM) avulsion between women who had undergone either Malmström vacuum delivery (MVD) or Kielland forceps delivery (KFD), allowing for potential confounding factors.

METHODS

This was a prospective observational study of nulliparous women undergoing instrumental delivery using Malmström vacuum extractor or Kielland forceps, at two hospital centers in Spain. Fetal head position (anterior, posterior or transverse) and fetal head station (low or mid) were assessed by ultrasound and digital examination, respectively. Avulsion was defined on tomographic ultrasound imaging as an abnormal insertion of the LAM in the three central slices from the plane of minimal hiatal dimensions.

RESULTS

In total, 414 patients were included in the study (212 MVD and 202 KFD). We observed a higher rate of LAM avulsion in the KFD group (KFD 49.5% vs MVD 32.5%; P = 0.001). When the results were evaluated according to fetal head position and station, we observed no differences in LAM avulsion. The crude odds ratio (OR) for the difference in avulsion between women in the KFD and MVD groups was 2.03 (95% CI, 1.36-3.03). However, when adjusted for duration of second stage of labor, fetal head circumference and fetal head station, the OR was no longer statistically significant (OR, 2.14 (95% CI, 0.95-4.85); P = 0.068).

CONCLUSION

When potential confounding factors are taken into account, the rate of LAM avulsion does not differ between women according to whether they have undergone KFD or MVD. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

A comparable rate of levator ani muscle injury in operative vaginal delivery (forceps and vacuum) according to the characteristics of the instrumentation

INTRODUCTION

Forceps delivery is associated with a high rate of levator ani muscle (LAM) trauma (avulsion) at 35%-65% whereas data on avulsion rates after vacuum delivery vary greatly. Nevertheless, a common characteristic of all previous studies carried out to evaluate the association between instrumental deliveries (forceps and vacuum) and LAM avulsion, is the fact that characteristics of the instrumentation have not been described or evaluated. The objective of this study is to compare the rate of LAM avulsion between forceps and vacuum deliveries according to the characteristics of the instrumentation.

MATERIAL AND METHODS

Prospective, observational study, including 263 nulliparous women, who underwent an instrumental delivery with either Malmström vacuum or Kielland forceps. The characteristics of the instrumentation, position (anterior position and other position) and height of the fetal head at the moment of instrumentation (low instrumentation [vertex at +2 station] and mid-instrumentation [head is involved but leading part above +2 station]) were assessed. Evaluation of LAM avulsion was performed at 6 months postpartum by three-/four-dimensional transperineal ultrasound. Using the multi-view mode, a complete avulsion was diagnosed when the abnormal muscle insertion was identified in all three central slices, that is, in the plane of minimal hiatal dimensions and the 2.5-mm and 5.0-mm slices cranial to this one. To detect a 30% or 15% difference in the LAM injury rate, with 80% power and 5% α-error, we needed, respectively 42 and 99 women per study group.

RESULTS

In all, 263 nulliparous individuals have been evaluated (162 vacuum deliveries, 101 forceps deliveries). Instrumentation in an occipito-anterior position was more frequent in vacuum deliveries (75.3% vs 56.4%, P = .002), whereas other positions were more frequent in the forceps deliveries group (24.7% vs 43.6%). No statistically significant differences were noted regarding the height of the fetal head at the moment of instrumentation. No statistically significant differences were found in the presence of LAM avulsion (41.4% vs 38.6%) between vacuum and forceps deliveries. The univariate analysis of the crude odds ratio was 1.17, 95% CI 0.67-1.98, P = .70 for the avulsion of the LAM and the multivariate of the adjusted OR 0.90, 95% CI; 0.53-1.55, P = .71.

CONCLUSIONS

We consider that, in our population, LAM avulsion rate should not be a factor taken into account when choosing the type of instrumentation (Malmström vacuum or Kielland forceps) in an operative delivery.

Delivery mode and the risk of levator muscle avulsion: a meta-analysis

INTRODUCTION AND HYPOTHESIS

Female pelvic organ prolapse (POP) is a common condition, with a lifetime risk for surgery of 10-20%. Pregnancy and childbirth are the commonest modifiable risk factors for POP, and avulsion of the levator ani muscle is likely to be an etiological factor. Avulsion is more common in instrumental delivery. However, we were unable to identify a meta-analysis on this issue. Our aim was to perform a systemic review and quantitative meta-analysis of the prevalence of avulsion relative to delivery mode.

METHODS

Four electronic databases (MEDLINE, PubMed, Embase, and Google Scholar) were searched for studies published between 1991 and 1 October 2018 without language restrictions.

RESULTS

Twenty studies met inclusion criteria, and 14 were prospective. Seventeen used sonographic techniques; three were magnetic resonance (MR) studies. For this review, three comparisons were performed: forceps vs. vacuum (9 studies), forceps vs. normal vaginal delivery (NVD) (12 studies), and vacuum vs. NVD (12 studies). The first meta-analysis showed an increased risk for avulsion following forceps compared with vacuum, with an odds ratio (OR) of 4.57 and confidence interval (CI) 3.21-6.51, p < 0.001. The second showed an increased risk for avulsion following forceps compared with NVD, with an OR of 6.94 (4.93-9.78), p < 0.001. The third showed no significant increased risk for avulsion following vacuum compared with NVD, with an OR of 1.31 (1.00-1.72), p = 0.051.

CONCLUSIONS

Forceps is a strong risk factor for avulsion, with an OR of 6.94 (4.93-9.78) compared with NVD and an OR of 4.57 (3.21-6.51) compared with vacuum birth.

Correlation Between Delivery Mode and Pelvic Organ Prolapse Evaluated by Four-Dimensional Pelvic Floor Ultrasonography

BACKGROUND This study explored symptoms and signs of pelvic organ prolapse (POP) evaluated by 4-dimensional pelvic floor ultrasonography and analyzed the relationship between delivery mode and POP. MATERIAL AND METHODS A total of 578 women who underwent 4-dimensional transperineal ultrasound were enrolled in this study. Obstetric history together with other clinical information were gathered from clinical questionnaires and gynecologists. Patients were thereafter classified into 4 groups: women with normal vaginal delivery, women with forceps delivery, women with cesarean, and nullipara women. We assessed symptoms and signs of POP among these 4 groups by use of 2 evaluation methods. The first method was clinical assessment applying International Continence Society (ICS) pelvic organ prolapse quantification (POP-Q). The second method was the use of ultrasonography in the quantification of anterior, middle, and posterior compartment prolapse. RESULTS Nulliparae women exhibited the lowest probability of POP (POP-Q: cystocele of 15.6%, uterine prolapse of 11.1%, rectocele of 20.0%; ultrasound exam: 6.7%, 8.9%, 13.3% in sequence), while women with forceps delivery had the highest probability of POP (POP-Q: 59.6%, 50.8%, 63.2% in sequence; ultrasound exam: 45.6%, 52.6%, 42.1% in sequence). Regarding the correlation between POP and delivery mode, the adjusted odds ratio was 2.40 (95%CI: 1.301~4.590) and 3.20 (95%CI: 1.651~6.121) in the normal vaginal delivery group and forceps group, respectively, compared with the cesarean group. CONCLUSIONS Four-dimensional pelvic floor ultrasonography can be used as a preferred method in evaluating POP. Regarding the relationship between delivery mode and POP, there is a significant correlation between vaginal delivery and POP.

Maternal birth trauma: why should it matter to urogynaecologists?

PURPOSE OF REVIEW

There is increasing awareness of the importance of intrapartum events for future pelvic floor morbidity in women. In this review, we summarize recent evidence and potential consequences for clinical practice.

RECENT FINDINGS

Both epidemiological evidence and data from perinatal imaging studies have greatly improved our understanding of the link between childbirth and later morbidity. The main consequences of traumatic childbirth are pelvic organ prolapse (POP) and anal incontinence. In both instances the primary etiological pathways have been identified: levator trauma in the case of POP and anal sphincter tears in the case of anal incontinence. As most such trauma is occult, imaging is required for diagnosis.

SUMMARY

Childbirth-related major maternal trauma is much more common than generally assumed, and it is the primary etiological factor in POP and anal incontinence. Both sphincter and levator trauma can now be identified on imaging. This is crucial not only for clinical care and audit, but also for research. Postnatally diagnosed trauma can serve as intermediate outcome measure in intervention trials, opening up multiple opportunities for clinical research aimed at primary and secondary prevention.

Longitudinal pelvic floor biometry: which factors affect it?

OBJECTIVES

To evaluate pelvic floor biometry of women 3-5 years after their first delivery. The effect of a subsequent delivery and the mode of delivery on pelvic floor biometry were also studied.

METHODS

Three-hundred and twenty-eight women who had been examined by translabial ultrasound during their first singleton pregnancy and at 8 weeks and 1 year postpartum, were invited for a follow-up 3-5 years later. The positions of the bladder neck, cervix, anorectal junction and hiatal area (HA) were evaluated using translabial ultrasound. The effects of parity, mode of delivery and levator ani muscle avulsion were studied.

RESULTS

A total of 240 women completed the study. Of these, 179 had one or more vaginal deliveries (VD) (VD-only group), 52 had one or more Cesarean sections (CS) (CS-only group) and nine had both VD and CS at follow-up. The mean interval between the first delivery and follow-up was 3.8 years. A significantly lower bladder neck and anorectal junction on Valsalva, a lower cervix at rest, on Valsalva and pelvic floor muscle contraction, and a greater HA were observed in the VD-only group at follow-up, compared with findings at 1 year of follow-up or in the first pregnancy. The findings were similar in the CS-only group, except without a lower anorectal junction on Valsalva. Compared with the primiparous VD-only group, a greater HA at rest was observed in the multiparous VD-only group (P = 0.027). The VD-only group had a greater HA than the CS-only group.

CONCLUSIONS

At 3-5 years after first delivery, a lower bladder neck, cervix and anorectal junction, and a greater HA were observed compared with findings in the first trimester and at 1 year of follow-up, regardless of parity or mode of delivery. Women with two or more VDs had a greater HA compared with those who had only one VD, and women with at least one VD had a greater HA compared with those who delivered by CS only. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Longitudinal follow-up of levator ani muscle avulsion: does a second delivery affect it?

OBJECTIVES

To evaluate the morphological outcome of levator ani muscle (LAM) avulsion 3-5 years after a first delivery and to assess the effect of a second delivery on this condition. The impact of LAM avulsion on pelvic floor disorders was also studied.

METHODS

Six hundred and sixty-six women who had been assessed for LAM avulsion 8 weeks after their first delivery were invited for a follow-up examination 3-5 years later. Women completed the Pelvic Floor Distress Inventory including the Urinary Distress Inventory (UDI) and Pelvic Organ Prolapse Distress Inventory (POPDI) questionnaires to explore symptoms of pelvic floor disorders, and the pelvic floor was examined using three-dimensional translabial ultrasound and assessed using the pelvic organ prolapse quantification system.

RESULTS

Three hundred and ninety-nine women completed the study, of whom 151 were multiparous. Mean interval between first delivery and follow-up was 42.3 ± 7.6 months. Among 69 women who had LAM avulsion 8 weeks after their first delivery, nine (13.0%) had no LAM avulsion at follow-up. One (0.9%) woman had a new LAM avulsion after her second vaginal delivery. A greater proportion of women with LAM avulsion reported symptoms of stress urinary incontinence (SUI) (adjusted odds ratio, 2.09 (95% CI, 1.18-3.70); P = 0.01) and symptoms of prolapse than did women without avulsion; however, this difference did not reach statistical significance (P = 0.61). Women with LAM avulsion had higher UDI and POPDI scores than did women without avulsion (median UDI score, 17.7 (interquartile range (IQR), 5.0-32.4) vs 9.2 (IQR, 0.0-22.1); P = 0.045 and median POPDI score, 20.8 (IQR, 8.8-40.5) vs 10.7 (IQR, 0.0-32.8); P = 0.021).

CONCLUSIONS

The risk of developing new LAM avulsion after a second vaginal delivery is low (0.9%). Healing of LAM avulsion was observed in 13% of women who had at least one vaginal delivery. At 3-5 years after delivery, women with LAM avulsion reported symptoms of SUI more often than did those without, and had higher UDI and POPDI scores, implying more bothersome symptoms. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Antenatal pelvic floor biometry is related to levator ani muscle injury

OBJECTIVE

To evaluate the relationship between antenatal pelvic floor biometry and levator ani muscle (LAM) injury in Chinese women.

METHODS

Three-dimensional transperineal ultrasound was performed in nulliparous Chinese women with a singleton pregnancy at 9-12 weeks, 26-28 weeks and 36-38 weeks of gestation and again at 12 months after delivery. Hiatal anteroposterior (AP) diameter, transverse diameter and area were measured on the antenatal ultrasound volumes obtained at rest, on Valsalva maneuver and during pelvic floor muscle contraction (PFMC). LAM injury was evaluated using ultrasound volumes obtained during PFMC at 12 months after delivery.

RESULTS

In total, 328 women completed the study. At 12 months after delivery, 38 (14.8% of those who delivered vaginally) women had LAM injury; 28 were unilateral (14 right- and 14 left-sided) and 10 were bilateral. In all three trimesters there was smaller hiatal AP diameter and hiatal area in women with LAM injury when compared with women without injury. On multivariable analysis of the three factors, hiatal AP diameter at rest, hiatal area at rest and operative vaginal delivery, only hiatal AP diameter at rest in all three trimesters was an independent factor of LAM injury. A larger hiatal AP diameter at rest in the first, second and third trimesters reduced the likelihood of LAM injury with odds ratios of 0.21, 0.15 and 0.21, respectively.

CONCLUSIONS

A smaller antenatal hiatal AP diameter at rest is a risk factor for LAM injury. The hiatal AP diameter is relatively simple to measure and the error in measurement is relatively small. A prospective study to confirm this relationship and to explore whether this measurement, performed in the midsagittal plane, is repeatable should be performed. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Does it matter whether levator avulsion is diagnosed pre- or postoperatively?

OBJECTIVE

Levator ani muscle avulsion is found in 15-30% of parturients and is associated with recurrence of pelvic organ prolapse (POP) following surgery, although most published evidence on recurrence relates to postoperative diagnosis. We performed a study to determine whether a diagnosis of avulsion after pelvic floor surgery can be used as a proxy for preoperative diagnosis.

METHODS

This was a retrospective study of 207 patients who were seen before and after surgery for POP between February 2007 and May 2013. All assessments included a three/four-dimensional transperineal tomographic ultrasound examination. Volume data were stored and analyzed at a later date by an operator who was blinded against all clinical data. The primary outcome measure was agreement between preoperative and postoperative diagnoses of avulsion, as evaluated by Cohen's kappa. Secondary outcome measures were the associations of pre- and postoperative diagnoses of levator avulsion with prolapse recurrence, defined as International Continence Society POP-Q Stage ≥ 2 in any compartment.

RESULTS

Mean follow-up after surgery was 1.3 (range, 0.3-5.5) years. Levator avulsion was found preoperatively in 111 (53.6%) patients and postoperatively in 109 (52.7%). The kappa value for the association between pre- and postoperative avulsion was 0.864 (95% CI, 0.796-0.933), signifying high agreement. The odds ratio of prolapse recurrence in women with a preoperative diagnosis of avulsion was 2.5 (95% CI, 1.3-4.5) and in those with a postoperative diagnosis it was 2.3 (95% CI, 1.3-4.2).

CONCLUSIONS

The diagnosis of levator avulsion by tomographic pelvic floor ultrasound is equally valid before and after pelvic reconstructive surgery for POP, and both diagnoses show excellent agreement. This implies that a postoperative diagnosis of avulsion can be used as a proxy for preoperative diagnosis. Hence, avulsion can be identified postoperatively and used for subgroup analysis in prospective surgical intervention trials to define high-risk patients. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Delivery mode and pelvic organ prolapse: a retrospective observational study

OBJECTIVE

To analyse the associations between delivery mode and symptoms and signs of pelvic organ prolapse (POP) in a cohort of symptomatic women.

DESIGN

Retrospective observational study.

POPULATION

A total of 1258 consecutive women attending a tertiary urogynaecological unit for the investigation of lower urinary tract or pelvic floor disorders between January 2012 and December 2014.

METHODS

Obstetric history and clinical examination data were obtained from the unit database. Prolapse quantification on imaging was performed using stored four-dimensional translabial ultrasound volume data sets. Women were grouped into four groups according to the most traumatic delivery reported. The presence of symptoms and signs of POP were compared between delivery groups while controlling for potential confounders.

MAIN OUTCOME MEASURES

Prolapse symptoms, visual analogue score for prolapse bother, International Continence Society Prolapse Quantification System findings and ultrasound findings of anterior, central and posterior compartment descent.

RESULTS

Nulliparae showed the lowest prevalence of most measures of POP, followed by women exclusively delivered by caesarean section. Highest prevalences were consistently found in women delivered at least once by forceps, although the differences between this group and women delivered by normal vaginal delivery and/or vacuum extraction were significant in three out of eight measures only. Compared with women in the caesarean section group, the adjusted odds ratios for reporting symptoms of prolapse were 2.4 (95% CI 1.30-4.59) and 3.2 (95% CI 1.65-6.12) in the normal vaginal delivery/vacuum extraction group and forceps group, respectively.

CONCLUSIONS

There is a clear link between vaginal delivery and symptoms and signs of pelvic organ prolapse in urogynaecological patients.

TWEETABLE ABSTRACT

Compared with caesarean section a history of vaginal delivery more than doubles the risk for POP.

Forceps delivery is associated with increased risk of pelvic organ prolapse and muscle trauma: a cross-sectional study 16-24 years after first delivery

OBJECTIVES

To study possible associations between mode of delivery and pelvic organ prolapse (POP) and pelvic floor muscle trauma 16-24 years after first delivery and, in particular, to identify differences between forceps and vacuum delivery.

METHODS

This was a cross-sectional study including 608 women who delivered their first child in 1990-1997 and were examined with POP quantification (POP-Q) and pelvic floor ultrasound in 2013-2014. Outcome measures were POP ≥ Stage 2 or previous prolapse surgery, levator avulsion and levator hiatal area on Valsalva. Univariable and multivariable logistic regression analyses and ANCOVA were applied to identify outcome variables associated with mode of delivery.

RESULTS

Comparing forceps to vacuum delivery, the adjusted odds ratios (aOR) were 1.72 (95% CI, 1.06-2.79; P = 0.03) for POP ≥ Stage 2 or previous prolapse surgery and 4.16 (95% CI, 2.28-7.59; P < 0.01) for levator avulsion. Hiatal area on Valsalva was larger, with adjusted mean difference (aMD) of 4.75 cm(2) (95% CI, 2.46-7.03; P < 0.01). Comparing forceps with normal vaginal delivery, the adjusted odds ratio (aOR) was 1.74 (95% CI, 1.12-2.68; P = 0.01) for POP ≥ Stage 2 or surgery and 4.35 (95% CI, 2.56-7.40; P < 0.01) for levator avulsion; hiatal area on Valsalva was larger, with an aMD of 3.84 cm(2) (95% CI, 1.78-5.90; P < 0.01). Comparing Cesarean delivery with normal vaginal delivery, aOR was 0.06 (95% CI, 0.02-0.14; P < 0.01) for POP ≥ Stage 2 or surgery and crude OR was 0.00 (95% CI, 0.00-0.30; P < 0.01) for levator avulsion; hiatal area on Valsalva was smaller, with an aMD of -8.35 cm(2) (95% CI, -10.87 to -5.84; P < 0.01). No differences were found between vacuum and normal vaginal delivery.

CONCLUSIONS

We found that mode of delivery was associated with POP and pelvic floor muscle trauma in women from a general population, 16-24 years after their first delivery. Forceps was associated with significantly more POP, levator avulsion and larger hiatal areas than were vacuum and normal vaginal deliveries. There were no statistically significant differences between vacuum and normal vaginal deliveries. Cesarean delivery was associated with significantly less POP and pelvic floor muscle trauma than were normal or operative vaginal delivery.

Characteristics associated with pelvic organ prolapse in women with significant levator ani muscle deficiency

INTRODUCTION AND HYPOTHESIS

Age is a factor associated with symptomatic pelvic organ prolapse (POP) among women with significant levator ani deficiency.

METHODS

This cross-sectional study included patients who were referred for varied pelvic floor disorders, had 3D endovaginal ultrasound as part of their evaluation, and were diagnosed with significant levator ani muscle deficiency defined as a score of 12 or more on 3D endovaginal ultrasound. Patients were categorized as having no pelvic organ prolapse (stages 0 and 1), or symptomatic prolapse (stages 2-4).

RESULTS

Seventy-six women were available for analysis and found to have significant levator ani muscle deficiency, including 51 with symptomatic POP and 25 without POP. Patients with symptomatic POP were older, (mean age 66 (SD ± 11.8) vs 48 (SD ± 17.3) years; p <0.0001), had greater mean minimal levator hiatus (MLH) area (19.7 cm(2) (SD ± 4.6) vs 17.5 cm(2) (SD ± 3.5); p = 0.048), and were more likely to be menopausal (91.3 % vs 54.5 %; p <0.001) compared with those with no POP. In a modified Poisson regression analysis excluding nulliparous women, increasing age (RR = 2.39, 95 % CI 1.03-5.55) and smoking (RR = 1.34, 95 % CI 1.08-1.67) remained associated with symptomatic POP after controlling for one another and the MLH area.

CONCLUSIONS

Among women with significant levator ani deficiency, older women and smokers had an increased prevalence of symptomatic POP. On average, women without POP, but with significant levator ani deficiency were 18 years younger than women with POP and significant muscle deficiency.

Forceps: towards obsolescence or revival?

Cesarean section rates have become a political issue, attracting the attention of governments, health bureaucrats and professional organizations. In some instances this has led to a renewed interest in forceps delivery, even Kielland's rotational forceps. It is suggested that calls for a greater use of forceps, especially rotational forceps, are ill-advised and commonly based on ignorance of recent urogynecological and imaging literature. Forceps use is associated with a much higher likelihood of major maternal trauma, especially to the anal sphincter and levator ani muscles, which may result in substantial future morbidity. Hence, its use should be avoided whenever possible. This is particularly obvious for rotational forceps.