Female Pelvic Floor Research Articles

Assessment of female pelvic floor support to the urethra using 3D transperineal ultrasound.

To explore the feasibility of three-dimensional (3D) transperineal tomographic ultrasound in evaluating pelvic floor support of the urethra in women. Three-dimensional transperineal ultrasound volume data sets of 50 women with stress urinary incontinence (SUI) and 25 women without SUI were obtained for analysis. Pelvic floor support of the urethra was evaluated by studying the relationship between the urethra and vagina in vaginal cross section and quantified by estimating the urethral depression (UD) rate. The extent of paravaginal support at level II was also evaluated in tomographic ultrasound imaging (TUI) mode in all participants. Two-sample t-test and Mann-Whitney U test were used for statistical analysis. The extent of paravaginal support at level II showed no difference between the two groups. Posterior depression of the urethra into the anterior vaginal wall was increased in SUI (P < 0.05). When the UD rate value was 0.53 (CI 85%) combined with three continuous "abnormal slices," the maximum Youden Index value (sensitivity 0.82, specificity 0.88) was obtained to screen dysfunctional support of the urethra. The pelvic floor support of the urethra can be evaluated indirectly by studying the relationship between the urethra and anterior vaginal wall in the vaginal cross section by TUI. The obvious posterior depression of the urethra into the anterior vaginal wall could be indirect evidence of a defect in the support of the urethra.

MP56-15 SCREENING FOR URINARY INCONTINENCE IN MINNESOTA WOMEN USING A VALIDATED EPIDEMIOLOGIC SURVEY: A CROSS-SECTIONAL STUDY

INTRODUCTION AND OBJECTIVES:The prevalence of female pelvic floor disorders (PFDs) including urinary incontinence (UI) is felt to be high, however prior estimates vary. Estimates range from 1% to 5...

Patient-Reported Outcome Measures (PROMs) in Pelvic Floor Disorders.

Patient-reported outcome measures (PROMs) are tools that are widely used by clinicians and researchers across different medical specialties. In this review, we examine the use of PROMs in the evaluation of female pelvic floor disorders (PFD). PROM development in the assessment of urinary incontinence is more advanced than other pelvic disorders. Work is ongoing in the scientific community to improve currently available measures and create new robust tools where needed. Hundreds of PROMs are available for use in the evaluation of PFD, some more rigorously validated than others. They are used to screen for diseases, evaluate their impact on quality of life, determine the results of treatment, and measure patient's satisfaction with treatment. Careful consideration is required to choose the appropriate PROMs to care for a patient or include in a research study. The topic was reviewed in the Textbook of Female Urology and Urogynecology published in 2017. We reviewed recent literature (2015-2018) on the topic and summarized our findings.

Computer Application of Ultrasound and Nuclear Magnetic Resonance Images for the Anatomical Learning of the Pelvis and the Female Pelvic Floor.

Computer applications have been incorporated as valuable components in teaching, especially thanks to the advancement and innovation of new technologies during the last decades. The implementation of these computer developments in medicine and in the field of medical teaching with different utilities has been a revolution. This is manifested with greater intensity in certain medical specialties and in different areas of medical education, for example in the study of human anatomy, especially in parts of the human body of great complexity such as the pelvis and the pelvic floor of women. New technologies are also important in the use, study and interpretation of radiological tests, including ultrasound and nuclear magnetic resonance. This implies a change in the study and learning techniques of students, resident doctors and specialists in gynecology, radiodiagnosis, urology and many other medical specialties, considering new computer developments as a good alternative or complement to existing teaching methods. For this reason, we consider that computer programs like the one we present in this work can be very useful in the future of education and more specifically in the training of specialists in medicine.

Task-specific differences in respiration-related activation of deep and superficial pelvic floor muscles.

The female pelvic floor muscles (PFM) are arranged in distinct superficial and deep layers that function to support the pelvic/abdominal organs and maintain continence, but with some potential differences in function. Although general recordings of PFM activity show amplitude modulation in conjunction with fluctuation in intra-abdominal pressure such as that associated with respiration, it is unclear whether the activities of the two PFM layers modulate in a similar manner. This study aimed to investigate the activation of the deep and superficial PFM during a range of respiratory tasks in different postures. Twelve women without pelvic floor dysfunction participated. A custom-built surface electromyography (EMG) electrode was used to record the activation of the superficial and deep PFM during quiet breathing, breathing with increased dead space, coughing, and maximal and submaximal inspiratory and expiratory efforts. As breathing demand increased, the deep PFM layer EMG had greater coherence with respiratory airflow at the frequency of respiration than the superficial PFM (P = 0.038). During cough, the superficial PFM activated earlier than the deep PFM in the sitting position (P = 0.043). In contrast, during maximal and submaximal inspiratory and expiratory efforts, the superficial PFM EMG was greater than that for the deep PFM (P = 0.011). These data show that both layers of PFM are activated during both inspiration and expiration, but with a bias to greater activation in expiratory tasks/phases. Activation of the deep and superficial PFM layers differed in most of the respiratory tasks, but there was no consistent bias to one muscle layer. NEW & NOTEWORTHY Although pelvic floor muscles are generally considered as a single entity, deep and superficial layers have different anatomies and biomechanics. Here we show task-specific differences in recruitment between layers during respiratory tasks in women. The deep layer was more tightly modulated with respiration than the superficial layer, but activation of the superficial layer was greater during maximal/submaximal occluded respiratory efforts and earlier during cough. These data highlight tightly coordinated recruitment of discrete pelvic floor muscles for respiration.

The impact of a familiarization session on the magnitude and stability of active and passive pelvic floor muscle forces measured through intravaginal dynamometry.

The aim of this study was to investigate the impact of task familiarization on (1) the magnitude and (2) the repeatability of active and passive properties of the female pelvic floor muscles (PFMs) measured using automated intra-vaginal dynamometry. Women attended three laboratory sessions at one-week intervals. After receiving initial task instruction and feedback at the start of the first session, standardized instructions were given while women performed maximal effort voluntary contractions of their PFMs with the dynamometer arms open at two different diameters and kept their PFMs relaxed while the dynamometer arms opened to 40 mm at two speeds. Outcomes included baseline force, peak force, relative peak forces (N), rate of force development (N/s) and stiffness. Between session effects were tested for all outcomes using one-way ANOVAs. Intra-class correlation coefficients (ICCs) and minimal detectable change values were computed within each session and between sessions 1 and 2 and sessions 2 and 3. Twenty nulliparous women (mean age = 35 ± 15 years) participated. No differences in the mean values were found across the three visits for any outcomes. Within sessions, neither ICC nor minimal detectable change differed among sessions and between-session ICC values were not different between visits 1 and 2 and visits 2 and 3. There is no evidence of a familiarization effect over a two-week period on the amplitude nor repeatability of dynamometric measures of active or passive PFM properties recorded from nulliparous women.

Effect of pelvic floor dysfunction on sexual function and quality of life in Chinese women of different ages: An observational study

The aim of the present study was to investigate the effect of female pelvic floor dysfunction on sexual function and quality of life among different age groups. An observational study was carried out on 648 patients with pelvic organ prolapse (POP) or/and stress urinary incontinence. We assessed female sexual function and quality of life through the Prolapse/Urinary Incontinence Sexual Questionnaire Short Form and Incontinence Quality of Life Scale before surgeries, respectively. Patients were assigned into different age groups. The mean age of all patients was 62.04 ± 9.39 years. A total of 436 patients had POP, 120 patients had stress urinary incontinence and the remaining patients had both. Although sexual frequency decreased with increasing age, 517 patients still remained sexually active. A total of 10.83% of the patients aged ≥70 years were still sexually active, and 8.51% of them had sex less than one time per month. The Prolapse/Urinary Incontinence Sexual Questionnaire Short Form score and sexual frequency decreased with increasing age. However, the Incontinence Quality of Life Scale score increased with increasing age. Patients with only POP and aged ≥70 years showed a higher Incontinence Quality of Life Scale score (P < 0.001). The present study showed that POP and stress urinary incontinence are common among older Chinese women, and re associated with decreased sexual satisfaction and quality of life in China. It suggests that the existing sexual requirement of these patients should also be reconsidered before surgical assessment. Doctors should take sexual satisfaction into consideration when choosing a personalized type of surgery to improve the patients' quality of life physiologically and psychologically. Geriatr Gerontol Int 2019; 19: 299-304.

Traduction française de la terminologie commune de l’International Urogynecological Association (IUGA) et de l’International Continence Society (ICS) relative à la prise en charge conservatrice et non pharmacologique des troubles pelvi-périnéaux de la femme

There has been an increasing need for the terminology for the conservative management of female pelvic floor dysfunction to be collated in a clinically-based consensus report. This report combines the input of members and elected nominees of the Standardization and Terminology Committees of two International Organizations, the International Urogynecological Association (IUGA) and the International Continence Society (ICS), assisted at intervals by many external referees. An extensive process of nine rounds of internal and external review was developed to exhaustively examine each definition, with decision-making by collective opinion (consensus). Before opening up for comments on the webpages of ICS and IUGA, five experts from physiotherapy, neurology, urology, urogynecology and nursing were invited to comment on the paper. A terminology report for the conservative management of female pelvic floor dysfunction, encompassing over 200 separate definitions, has been developed. It is clinically-based with the most common symptoms, signs, assessments, diagnoses and treatments defined. Clarity and user-friendliness have been key aims to make it interpretable by practitioners and trainees in all the different specialty groups involved in female pelvic floor dysfunction. Ongoing review is not only anticipated but will be required to keep the document updated and as widely acceptable as possible. A consensus-based terminology report for the conservative management of female pelvic floor dysfunction has been produced aimed at being a significant aid to clinical practice and a stimulus for research.

91: Biomechanical mapping of pelvic floor restoration after prolapse surgery

The objective of this study is to explore biomechanical transformations of the female pelvic floor after pelvic organ prolapse (POP) surgeries. The prospective multi-center Phase III clinical trial (NCT02925585) was designed to explore changes in tissue elasticity, pelvic support structure strengths and pelvic muscle functions after POP surgeries. To date, 105 subjects were enrolled at five clinical sites, each with planned surgical procedures as the best fit proposed for the specific pelvic conditions by an urogynecologist and accepted by the patient. The applied surgical procedure set includes: supracervical hysterectomy, total hysterectomy, sacrocolpopexy, uterosacral ligament suspension, anterior and posterior colporrhaphy with and without graft augmentation, enterocele repair and perineorrhaphy. A Vaginal Tactile Imager (VTI) was used to acquire comprehensive data for biomechanical mapping of the pelvic floor. The VTI measurements were completed at rest with manually applied deflection pressures to vaginal walls and with pelvic muscle contractions. An analytical software package allowed automated computation of 52 biomechanical parameters for 8 VTI test procedures: (1) probe insertion, (2) elevation, (3) rotation, (4) Valsalva maneuver, (5-6) voluntary muscle contractions in 2 planes, (7) relaxation, and (8) reflex contraction at cough. Patient pelvic pre- and post-operative (4+ months) conditions and VTI data were analyzed to identify statistically significant changes in the biomechanical parameters by paired t-test. Interim analysis of 137 completed to date POP surgical procedures on 54 subjects demonstrates that 25 of 52 biomechanical parameters have statistically significant changes (p<0.05) with identified surgical procedures. A wide range of patient demographics across geographic regions and uses of a range of surgical approaches was observed. The proposed biomechanical mapping data are being integrated into a mathematical model to predict outcome of a surgical treatment based on the patient-specific pelvis clinical history/conditions and VTI preoperative examination results. This study represents the largest set of pelvic biomechanical data collected prospectively before and after POP surgery to date. The observed changes in parameters collected before and after the POP surgery suggest that the proposed biomechanical mapping could be effectively used to complement other diagnostic approaches and aid in choice of indication and assessment of the intervention across varied clinical conditions and procedures.

Pelvic floor muscle activity during impact loads in continent and incontinent women: A systematic review

Introduction: Investigating electromyographic activity of female pelvic floor muscle (PFM) during impact loads helps to clarify the pathophysiology of stress urinary incontinence (SUI).

Multimodal imaging assessment and histologic correlation of the female rat pelvic floor muscles’ anatomy

Pelvic floor disorders negatively impact millions of women worldwide. Although there is a strong epidemiological association with childbirth, the mechanisms leading to the dysfunction of the integral constituents of the female pelvic floor, including pelvic floor skeletal muscles, are not well understood. This is in part due to the constraints associated with directly probing these muscles, which are located deep in the pelvis. Thus, experimental models and non-invasive techniques are essential for advancing knowledge of various phenotypes of pelvic floor muscle injury and pathogenesis of muscle dysfunction, as well as developing minimally invasive approaches for the delivery of novel therapeutics. The most widely used animal model for pelvic floor disorders is the rat. However, the radiological anatomy of rat pelvic floor muscles has not been described. To remedy this gap, the current study provides the first detailed description of the female rat pelvic floor muscles' radiological appearance on MR and ultrasound images, validated by correlation with gross anatomy and histology. We also demonstrate that ultrasound guidance can be used to target rat pelvic floor muscles for possible interventional therapies.

Quantitative Evaluation of Female Pelvic Floor Muscle Biomechanics Using Ultrasound Elastography

Female pelvic floor dysfunction is a common disease which has become one of the five common chronic diseases threatening women's health. As the supporting structures, pelvic floor muscle is critical to support the pelvic organs, maintain continence, and prevent prolapse. The quantitative evaluation of pelvic floor muscle biomechanics is of great value for the diagnosis and treatment of female pelvic floor dysfunction. Our study aims to propose a noninvasive, quantitative, and objective method for motion analysis of the pelvic floor muscles. Ultrasound data, force data during continuous contractive activities from 37 subjects are synchronously collected using an ultrasound scanner and a self-designed intravaginal pressure acquisition device. A two-dimensional motion tracking algorithm is used to monitor the displacement of the pelvic floor muscles. The muscle displacement field is then computed. The parameter, defined as M pu , which is the tangential displacements of one interested point near pubis shows good correlation with clinical measurement parameter (L BP ) (r = -0.93, P <; 0.05). The continuous control ability of the pelvic muscles is further evaluated by measuring the average maintaining time of the maximal contraction force and the muscle thickness during this maintaining period. Both of them are well correlated with the clinical grading results of prolapse. It is concluded that the ultrasound measurements of tissue motions and biomechanics are of great value for the clinical pelvic floor prolapse diagnosis.

Current Treatments for Female Pelvic Floor Dysfunctions.

As global population aging, the issue of pelvic floor dysfunctions becomes increasingly. Millions of women were affected every year. The treatment of pelvic floor dysfunction has evolved in the past decade. This review aims to provide the current information on the treatment for female pelvic floor dysfunction, including pelvic organ prolapse (POP), urinary, fecal incontinence (FI), and myofascial pelvic pain among women. We used PubMed, Embase, and Web of Science to search for studies that were related to pelvic floor dysfunction regarding the POP, urinary, FI, and treatments. The development of laparoscopic surgery and synthetic and biological materials for pelvic floor reconstructive surgery were summarized. The surgical outcomes and complications of different pelvic floor reconstructive surgeries were compared. New devices for FI and the potential modified pelvic floor reconstructive surgery were also discussed here. Female pelvic medicine will continue to evolve for better treatment in the future. The pelvic floor reconstructive surgery tends to be minimally invasive approach with synthetic graft use.

Pelvic floor ultrasound: Essentials

Female pelvic floor dysfunction encompasses a number of prevalent conditions and includes pelvic organ prolapse, urinary and fecal incontinence, obstructed defecation and sexual dysfunction. In most cases neither etiology nor pathophysiology are well understood. Imaging has great potential to enhance both research and clinical management capabilities, and to date this potential is under-utilised. Of the available techniques such as X-ray, computed tomography, magnetic resonance imaging and ultrasound, the latter is generally superior for pelvic floor imaging, especially in the form of perineal or translabial imaging. The technique is safe, simple, cheap, easily accessible and provides high spatial and temporal resolutions. The commonest indication for pelvic floor imaging is female pelvic organ prolapse. Translabial realtime ultrasound during a Valsalva maneuver will demonstrate cystocele, uterine prolapse, rectocele, enterocele and rectal intussusception and allow quantification against the inferoposterior symphyseal margin. The introduction of 3D/4D imaging has allowed us to diagnose major pelvic floor trauma (‘avulsion’) and overdistension of the levator hiatus (‘ballooning’) reliably and accurately. Both are major etiological factors in the pathogenesis of pelvic organ prolapse and can be detected using equipment that is commonly available in O/G imaging departments. Women with avulsion and/ or major degrees of hiatal overdistension are at an increased risk of prolapse recurrence after reconstructive surgery. Identifying such pathology will not just allow a more realistic discussion of operative options, especially as regards mesh use, but has already opened up opportunities for entirely novel surgical approaches such as levator reconstruction and hiatal reduction. Most recently, translabial 4D imaging of the anal sphincter has made the assessment of anal incontinence simpler and less invasive. This technique will allow universal audits of of OASIS repair and eventually of obstetric management in general, enabling the introduction of ‘maternal birth trauma’ as a key performance indicator of obstetric services.

The short-term outcome of laser in the management of female pelvic floor disorders: Focus on stress urine incontinence and sexual dysfunction

ObjectiveFemale pelvic floor disorders, including female stress urinary incontinence (SUI) or sexual dysfunction are notorious for affecting the quality of women's life. It is reported that laser therapy might result in collagen remodeling and improvement in tissue firmness. The study was conducted to evaluate the short-term outcome of female pelvic floor disorders treated by laser therapy. Materials and methodsWomen with self-reported symptoms of female pelvic floor disorders (limited to SUI and sexual dysfunction) were included in the study. The participants were treated with the Er:YAG laser or the fractional microablative carbon dioxide (CO2) laser system. The therapeutic effect was focused on SUI symptoms and sexual dysfunction. ResultsThere were 31 women underwent laser treatment, including 21 patients treated with Erbium:YAG laser and 10 treated with CO2 laser. In the Erbium:YAG laser group, International Consultation on Incontinence Questionnaire – Urinary Incontinence Short Form (ICIQ- SF) scores were dropped from 8.25 ± 5.66 to 5.00 ± 3.99 (P = 0.007); and in the CO2 laser group, scores were dropped from 11.11 ± 6.85 to 6.44 ± 4.25 (P = 0.035), contributing to the drop of ICI-Q-SF scores from 9.14 ± 6.08 to 5.45 ± 4.05 for all enrolled patients (P = 0.001). However, objective measure using pad test did not show a statistically significant difference between before and after treatment (from 3.20 ± 5.84 g to 1.54 ± 3.18 g, P = 0.224). Sexual dysfunction was improved in 13 patients (44.83%), but Female Sexual Function Index (FSFI) scores were not different before and after laser treatment (44.22 ± 23.36 vs. 44.09 ± 24.51, P = 0.389). ConclusionLaser therapy either by Erbium:YAG laser or CO2 laser seemed to be useful for female pelvic floor disorders, especially on improvement of SUI symptoms; however, the effectiveness needs further confirmation.

Gentle cyclic straining of human fibroblasts on electrospun scaffolds enhances their regenerative potential

The extracellular matrix of fascia-like tissues is a resilient network of collagenous fibers that withstand the forces of daily life. When overstretched, the matrix may tear, with serious consequences like pelvic organ prolapse (POP). Synthetic implants can provide mechanical support and evoke a host response that induces new matrix production, thus reinforcing the fascia. However, there is considerable risk of scar formation and tissue contraction which result in severe complications. Matrix producing fibroblasts are both mechanosensitive and contractile; their behavior depends on the implant’s surface texture and mechanical straining. Here we investigate the effect of both in a newly-designed experimental setting.Electrospun scaffolds of Nylon and PLGA/PCL and a non-porous PLGA/PCL film were clamped like a drumhead and seeded with fibroblasts of POP patients. Upon confluency, scaffolds were cyclically strained for 24 or 72 h at 10% and 0.2 Hz, mimicking gentle breathing. Non-loading condition was control. Strained fibroblasts loosened their actin-fibers, thereby preventing myofibroblastic differentiation. Mechanical loading upregulated genes involved in matrix synthesis (collagen I, III, V and elastin), matrix remodeling (α-SMA, TGF-β1, MMP-2) and inflammation (COX-2, TNF-α, IL8, IL1-β). Collagen genes were expressed earlier under mechanical loading and the ratio of I/III collagen increased. Matrix synthesis and remodeling were stronger on the electrospun scaffolds, while inflammation was more prominent on the non-porous film. Our findings indicate that mechanical straining enhances the regenerative potential of fibroblasts for the regeneration of fascia-type tissues and limit the risk of scar tissue formation. These effects are stronger on an electrospun texture. Statement of significancePelvic organ prolapsed is a dysfunctional disease in female pelvic floor that can reduce the quality of life women. Currently, trans-vaginal knitted meshes are used to anatomically correct the dysfunctional tissues. However, the meshes can create sever adverse complications in some patients (e.g. chronic pain) in longer-term. As an alternative, we developed nanofibrous matrices by electrospinning based on different materials. We designed an in-vitro culture system and subjected cell-seeded matrices to cyclic mechanical loading. Results revealed that gentle straining of POP-cells on electrospun matrices, advances their regenerative potential at morphological and gene expression levels. Our findings, provide a proof-of-concept for using electrospun matrices as an alternative implant for pelvic floor repair, given that the parameters are designed efficiently and safely.

Characterizing pelvic floor muscles activities using magnetomyography.

To characterize levator ani muscle (LAM) activity in nulligravidas using magnetomyography (MMG) and define MMG characteristics associated with LAM activity with and without accessory muscle contributions. MMG data were collected from eight nulligravidas during rest and voluntary LAM contractions (Kegels) of varying intensity. We utilized simultaneous vaginal manometry and surface electromyography (sEMG) to evaluate for accessory muscle recruitment. Moderate Kegel (MK) MMG trials were sub-selected based on the presence or absence of accessory muscle interaction. Amplitude and spectral-related indicators were calculated across MK epochs: root-mean square (RMS) amplitude, percentage amplitude relative to rest, and relative power spectrum density (rPSD) in three frequency bands (low, middle, high). Ternary diagram characterized rPSD from selected Kegels and ROC analysis was performed to identify cut-points to differentiate MKs from interacting MKs. Nineteen MMG recordings were obtained. Amplitude and spectral parameters were significantly different between isolated and interacting MK epochs. Mean RMS and power values of the isolated MK were, respectively, 120.66 ± 43.8 fT and 1.72 ± 1.44 (T2 /Hz)*10-28 . Amplitudes of MK were 64% and 117 higher than baseline activities for the isolated and interacting epochs, respectively. ROC curves reveled cut-off points on low and middle frequency bands that achieved perfect separation (ROC-AUC = 1.0) between isolated and interacting MK. Our study demonstrates that MMG, a novel biomagnetic technique, allows precise detection and characterization of normal female pelvic floor function. Results show that isolated moderate voluntary contraction of the LAMs produces distinct MMG amplitude and spectral characteristics compared with Kegels involving co-activation of other muscle groups.

47] Management and outcomes of mesh complications in female pelvic floor surgery: Results of the York Mesh Salvage Centre

ObjectiveTo review the management and outcome of complications (erosion, extrusion, pain and obstruction) following urinary incontinence (UI) surgery. Stress UI (SUI) has been treated with synthetic mesh and implants procedures for >20 years with good success rates. A recent review indicated safety and efficacy of mid-urethral slings (MUS) for women with SUI. With increasing public and legal interest in litigation cases related to mesh complications, there is a growing need for surgeons to share their experiences to establish best practice care. York is one of the nationally recognised salvage centres for management of women with mesh-related problems.

Progress in maternal pelvic floor muscle training

Pelvic floor muscle training is an important means for preventing and treating pelvic floor dysfunction. This article reviews the impact of gestational delivery on pelvic floor function, the role of pelvic floor muscle training, the current status of maternal pelvic floor muscle training, influencing factors, and the progress of interventions. It is suggested that medical staff should strengthen the health education of the pelvic floor muscle training for pregnant women and the compliance and standardization of maternal pelvic floor muscle training, so as to reduce the incidence of female pelvic floor dysfunction diseases and protect women′s health. Key words: Maternal; Pelvic floor muscle training; Compliance

2D USS of the pelvic floor in the 3rd trimester versus mode of delivery

ObjectiveBiomechanics of pelvic floor muscles is becoming an important field of research in understanding a complex process of labour. Current evidence indicates that the levator ani stretches to allow passage of the fetus through the birth canal. We sought to identify properties of the functional female pelvic floor during pregnancy that could help to predict the mode of delivery, especially in women who underwent caesarean section in the past. MethodsA single centre prospective cohort study of pregnant women in the 3rd trimester attending antenatal clinic. Participants were categorised into three groups: 1. nulliparous, 2. previous one vaginal delivery and 3. previous one caesarean section who chose a trial of labour in their current pregnancy. All women underwent ultrasonographic evaluation of their pelvic floor muscles. Distensibility and the mode of delivery were assessed in participants’ current pregnancies. The primary outcome was the mode of delivery. ANOVA test was used for statistical analysis. Results133 women were included: 55 nulliparous, 52 primiparous (previous one vaginal birth), and 26 primiparous (previous one LSCS and planned for vaginal delivery after caesarean (VBAC)). Participants were scanned at an average gestation of 32 weeks. The inter-observer reliability test for puborectalis distensibility was good (kappa 0.75).Overall, women who delivered vaginally had a more distensible puborectalis muscle than those who delivered by emergency LSCS regardless of their previous type of delivery. Women who underwent a successful VBAC had less distensible pelvic floor muscles compared to their nulliparous and primiparous counterparts (who delivered vaginally in the past). ConclusionThese results support our basic conceptual theory of puborectalis muscle distensibility influencing the mode of delivery and endorse application of dynamic pelvic floor ultrasound in future studies. We identified measurable differences in the functional female pelvic anatomy aiding a better understanding of physiology of the labour. There are trends towards lesser distensibility in women who delivered by LSCS.