Investigating the association of the dimensions of genital hiatus and levator hiatus with pelvic organ prolapse: a systematic review

Association between enlarged genital hiatus and prolapse with overactive bladder 1 year after vaginal delivery

BACKGROUND

Genital hiatus enlargement is associated with pelvic organ prolapse and overactive bladder 5 to 10 years after first delivery. It is unknown if this association is present earlier postpartum.

OBJECTIVE

This study aimed to understand the association between overactive bladder within 1 year after first vaginal delivery and (1) enlarged genital hiatus, (2) anatomic pelvic organ prolapse, and (3) bulge symptoms.

STUDY DESIGN

This is a secondary analysis of a prospective cohort study of primiparous women with a singleton term vaginal delivery who completed symptom questionnaires and physical examinations at the third trimester and 8 weeks and 1 year postpartum. We defined overactive bladder as the presence of urinary urgency plus urinary frequency or nocturia, or urgency incontinence on the Epidemiology of Prolapse and Incontinence Questionnaire. Enlarged genital hiatus was defined as ≥4 cm, and anatomic pelvic organ prolapse was defined as vaginal descent at or beyond the hymen. We evaluated associations of overactive bladder with genital hiatus and pelvic organ prolapse at 1 year postpartum using Poisson regression.

RESULTS

We included 579 people with a mean age of 29 years; 17% were Hispanic. In separate models, enlarged genital hiatus and anatomic pelvic organ prolapse at 1 year postpartum were each associated with increased overactive bladder prevalence at 1 year postpartum (genital hiatus: adjusted risk ratio, 1.5; 95% confidence interval, 1.1-2.1; pelvic organ prolapse: adjusted risk ratio, 1.8; 95% confidence interval, 1.2-2.6). These effects were greater among women aged ≥30 years (genital hiatus: adjusted risk ratio, 2.1; 95% confidence interval, 1.3-3.4; pelvic organ prolapse: adjusted risk ratio, 2.2; 95% confidence interval, 1.3-3.7) and were not significant among women aged <30 years.

CONCLUSION

Enlarged genital hiatus and pelvic organ prolapse at 1 year postpartum are associated with overactive bladder at as early as 1 year postpartum, particularly among women aged ≥30 years. Genital hiatus may be a marker of pelvic floor function that, when impaired, increases the risk of pelvic organ prolapse and overactive bladder after delivery.

Clinically significant changes in anal sphincter hiatal area in patients with gestational diabetes mellitus and pelvic organ prolapse

BACKGROUND

The prevalence of pelvic organ prolapse (POP) increases with age and parity. Specifically, the prevalence of POP among women aged 20 to 39 is 9.7%, while it rises to 49% among women over 80 years old. Additionally, as the number of deliveries increases, the prevalence of POP also rises accordingly, with a rate of 12.8% for women with one delivery history, 18.7% for those with two deliveries, and 24.6% for women with three or more deliveries. It causes immense suffering for pregnant women.

AIM

To evaluate the relationship between the levator ani muscle's hiatus (LH) area and POP in patients with gestational diabetes mellitus (GDM) using perineal ultra-sound.

METHODS

The study cohort comprised 104 patients aged 29.8 ± 3.7 years who sought medical care at our institution between January 2021 and June 2023. All were singleton pregnancies consisting of 75 primiparas and 29 multiparas, with an average parity of 1.7 ± 0.5. According to the POP diagnostic criteria, the 104 subjects were divided into two groups with 52 members each: POP group (patients with GDM combined with POP) and non-POP group (patients with GDM without POP). Perineal ultrasound was used to measure differences in the anteroposterior diameter, transverse diameter, and LH area. Receiver operating characteristic curves were drawn to determine the optimal cutoff values for the LH anteroposterior diameter, transverse diameter, and area for diagnosing POP.

RESULTS

Statistically significant increase in the LH area, anteroposterior diameter, and lateral diameter were observed in the POP group compared with the non-POP group (P < 0.05). Both groups exhibited markedly elevated incidence rates of macrosomia and stress urinary incontinence. For the POP group, the area under the curve (AUC) for the LH area was 0.906 with a 95% confidence interval (CI): 0.824-0.988. The optimal cutoff was 13.54cm², demonstrating a sensitivity of 83.2% and a specificity of 64.4%. The AUC for the anteroposterior diameter reached 0.836 with a 95%CI: 0.729-0.943. The optimal cutoff was 5.53 cm with a sensitivity of 64.2% and a specificity of 73.4%. For the lateral diameter, its AUC was 0.568 with a 95%CI: 0.407-0.729. The optimal cutoff was 4.67 cm, displaying a sensitivity of 65.9% and a specificity of 69.3%. Logistic regression analysis unveiled that age, body weight, number of childbirths, total number of pregnancies, and gestational weight gain constituted the independent risk factors for the cooccurrence of GDM and POP.

CONCLUSION

Three-dimensional perineal ultrasonography of LH size and shape changes can effectively diagnose POP. Age, weight, number of births, number of pregnancies, and weight gain during pregnancy are independent risk factors affecting the cooccurrence of GDM and POP. GDM can increase the LH area in patients, and an enlarged LH leads to an increased incidence of POP.

Improving radiological quantification of levator hiatus features with measures informed by statistical shape modeling

Purpose

The measures that traditionally describe the levator hiatus (LH) are straightforward and reliable; however, they were not specifically designed to capture significant differences. Statistical shape modeling (SSM) was used to quantify LH shape variation across reproductive-age women and identify novel variables associated with LH size and shape.

Approach

A retrospective study of pelvic MRIs from 19 nulliparous, 32 parous, and 12 pregnant women was performed. The LH was segmented in the plane of minimal LH dimensions. SSM was implemented. LH size was defined by the cross-sectional area, maximal transverse diameter, and anterior-posterior (A-P) diameter. Novel SSM-guided variables were defined by regions of greatest variation. Multivariate analysis of variance (MANOVA) evaluated group differences, and correlations determined relationships between size and shape variables.

Results

Overall shape ( p < 0.001 ), SSM mode 2 (oval to T -shape, p = 0.002 ), mode 3 (rounder to broader anterior shape, p = 0.004 ), and maximal transverse diameter ( p = 0.003 ) significantly differed between groups. Novel anterior and posterior transverse diameters were identified at 14% and 79% of the A-P length. Anterior transverse diameter and maximal transverse diameter were strongly correlated ( r = 0.780 , p < 0.001 ), while posterior transverse diameter and maximal transverse diameter were weakly correlated ( r = 0.398 , p = 0.001 ).

Conclusions

The traditional maximal transverse diameter generally corresponded with SSM findings but cannot describe anterior and posterior variation independently. The novel anterior and posterior transverse diameters represent both size and shape variation, can be easily calculated alongside traditional measures, and are more sensitive to subtle and local LH variation. Thus, they have a greater ability to serve as predictive and diagnostic parameters.

Analysis of minimal levator ani hiatus area based on MRI in female adults without pelvic floor dysfunction at different age groups

PURPOSE

To investigate the association of minimal levator ani hiatus area with age in female adults without pelvic floor dysfunction.

METHODS

532 female subjects aged 18 ~ 90 years without pelvic floor dysfunction, divided into four groups (Group A, 18 ~ 29 years old; Group B, 30 ~ 39 years old; Group C, 40 ~ 49 years old; Group D, ≥ 50 years old) based on age, underwent traditional pelvic two-dimensional (2D) T2-weighted imaging (T2WI) axial to the body (AxB) for measuring the minimal levator ani hiatus area. 39 female volunteers were re-recruited to undergo both traditional pelvic 2D T2WI AxB and three-dimensional (3D) T2WI. An axial plane parallel to the direction of the puborectalis muscle (AxPRM) was acquired based on 3D T2WI. The difference of levator ani hiatus area measured on AxB and AxPRM images in 39 female volunteers was compared by one-sample t test, to verify if minimal levator ani hiatus area can be acquired on the traditional pelvic 2D T2WI AxB images. Spearman analysis evaluated the association of minimal levator ani hiatus area with age and the rank-sum test analyzed the area differences among four age groups.

RESULTS

Female age was positively correlated with minimal levator ani hiatus area (r = 0.23; p < 0.001). The minimal levator ani hiatus areas of 532 subjects were: 15.17 ± 1.77 cm2 in Group A, 15.52 ± 2.21 cm2 in Group B, 16.03 ± 2.16 cm2 in Group C, and 16.40 ± 2.10 cm2 in Group D. ANOVA showed significant statistical differences among four age groups (F = 7.519, p < 0.0001). Significant differences in minimal levator ani hiatus areas were found between Group A and Group C (p = 0.0491), Group A and Group D (p = 0.0007), and Group B and Group D (p < 0.001). There was no statistical difference in minimal levator ani hiatus areas measured on AxB and AxPRM images in 39 female volunteers (p = 0.1000). There were no statistical difference in minimal levator ani hiatus areas between nulliparous and multiparous group for each age group (all p > 0.05).

CONCLUSIONS

Based on a large sample, this study summarized the minimum levator ani hiatus area of female adults without pelvic floor dysfunction in different age groups. We found significant differences among different age groups. In addition, a positive correlation was found between age and the minimum levator ani hiatus area. These findings can provide reference criteria for diagnosing pelvic organ prolapse in female adults of different age groups.

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

Objective

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

Methods

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

Results

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

Conclusion

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

Multimodal measurements of levator bowl volume in nulligravid asymptomatic women: endovaginal ultrasound versus MRI

INTRODUCTION AND HYPOTHESIS

Measurements of levator bowl volume using advanced imaging, may be predictive of pelvic floor muscle function. The aim of this study was to compare the volume of the levator bowl using both magnetic resonance imaging (MRI) and endovaginal ultrasound (EVU) of healthy asymptomatic women.

METHODS

All participants underwent a comprehensive interview including completion of the Pelvic Floor Distress Inventory Questionnaire-20 questionnaire, pelvic examination with a pelvic organ prolapse quantification evaluation, MRI, and EVU. The pelvic floor was segmented using Slicer and the MRI segmentations were trimmed using two methods: soft-tissue landmarks and the field of view (FOV) of the ultrasound volume. The levator bowl volume of the 3D segmented shapes was measured using Blender's 3D printing toolkit. Normality was tested using the Shapiro-Wilks test and comparisons were made using self-paired t tests.

RESULTS

The final analysis included 19 patients. Levator bowl volume measured via MRI was larger than that measured in EVU (46.1 ± 7.9 cm3 vs 27.4 ± 5.9 cm3, p<0.001). Reducing the FOV of the MRI to that of EVU caused the MRI volume to be much closer to the EVU volume (35.5 ± 3.3 cm3 vs 27.4 ± 5.9 cm3, p<0.001); however, it remained significantly larger.

CONCLUSION

Levator bowl volume measured using MRI was larger than that measured using EVU no matter the method of delineation of the levator muscles. Although EVU is safe, cheap, and easy to perform, it captures a smaller volume of levator bowel than MRI.

International urogynecology consultation chapter 3 committee 2; conservative treatment of patient with pelvic organ prolapse: Pelvic floor muscle training

INTRODUCTION AND HYPOTHESIS

This manuscript from Chapter 3 of the International Urogynecology Consultation (IUC) on Pelvic Organ Prolapse (POP) describes the current evidence and suggests future directions for research on the effect of pelvic floor muscle training (PFMT) in prevention and treatment of POP.

METHODS

An international group of four physical therapists, four urogynecologists and one midwife/basic science researcher performed a search of the literature using pre-specified search terms on randomized controlled trials (RCTs) in Ovid Medline, EMBASE, CINAHL, Cochrane, PEDro and Scopus databases for publications between 1996 and 2021. Full publications or expanded abstracts in English or in other languages with abstracts in English were included. The PEDro rating scale (0-10) was used to evaluate study quality. Included RCTs were reviewed to summarize the evidence in six key sections: (1) evidence for PFMT in prevention of POP in the general female population; (2) evidence for early intervention of PFMT in the peripartum period for prevention and treatment of POP; (3) evidence for PFMT in treatment of POP in the general female population; (4) evidence for perioperative PFMT; (5) evidence for PFMT on associated conditions in women with POP; (6) evidence for the long-term effect of PFMT on POP. Full publications in English or in other languages with abstracts in English and expanded abstracts presented at international condition specific societies were included. Internal validity was examined by the PEDro rating scale (0-10).

RESULTS

After exclusion of duplicates and irrelevant trials, we classified and included 2 preventive trials, 4 trials in the post-partum period, 11 treatment trials of PFMT for POP in the general female population in comparison with no treatment or lifestyle interventions, 10 on PFMT as an adjunct treatment to POP surgery and 9 long-term treatment trials. Only three treatment studies compared PFMT with the use of a pessary. The RCTs scored between 4 and 8 on the PEDro scale. No primary prevention studies were found, and there is sparse and inconsistent evidence for early intervention in the postpartum period. There is good evidence/recommendations from 11 RCTs that PFMT is effective in reducing POP symptoms and/or improving POP stage (by one stage) in women with POP-Q stage I, II and III in the general female population, but no evidence from 9/10 RCTs that adding PFMT pre- and post -surgery for POP is effective. There are few long-term follow-up studies, and results are inconsistent. There are no serious adverse effects or complications reported related to PFMT.

CONCLUSIONS

There are few studies on prevention and in the postpartum period, and the effect is inconclusive. There is high-level evidence from 11 RCTs to recommend PFMT as first-line treatment for POP in the general female population. PFMT pre- and post-POP surgery does not seem to have any additional effect on POP. PFMT is effective and safe but needs thorough instruction and supervision to be effective.

What Influences Women to Adhere to Pelvic Floor Exercises after Physiotherapy Treatment? A Qualitative Study for Individualized Pelvic Health Care

Conservative treatment of pelvic floor dysfunction (PFD) includes therapeutic exercise for pelvic floor muscle (PFM) training or other complementary exercise modalities, such as hypopressive exercises. However, the long-term effectiveness of the conservative treatment depends on a patient's adherence to the exercises and the integration of professional health advice into their daily life. The objective of this study was to establish the adherence experience of women with diagnosed PFD in home-based exercises after an intensive face-to-face physiotherapy treatment. A qualitative study from an interpretive paradigm was developed. Semi-structured individual and group interviews were performed 6 months after finishing individual physiotherapy treatment. The interviews were recorded, fully transcribed and analyzed thematically by creating categories. Thirty-one women were interviewed. The women reported that their adherence to home PFM exercises depended on the exercise program itself, its efficacy, their personal experiences with the exercises, intrinsic factors such as self-awareness or beliefs, and extrinsic factors, such as professional or instrumental feedback. Thus, therapeutic adherence could be more likely with effective physiotherapy programs that include mutually agreed home exercises and simple movements women can build into their daily lives. Improving awareness and knowledge of the pelvic region and the importance of PFM treatment as well as consideration for potential worsening of PFD will also encourage women to adhere to the exercises.