Pelvic floor muscle variables and levator hiatus dimensions: a 3/4D transperineal ultrasound cross-sectional study on 300 nulliparous pregnant women

Return to Running for Postpartum Elite and Subelite Athletes

CONTEXT

There is little evidence to guide elite athletes who desire returning to competition after giving birth to a child. Ultimately, this can result in decreased performance and increased risk of injury. This paper addresses aspects that must be considered when building and monitoring a return to running program for a postpartum elite or subelite athlete, including pelvic floor and core stability, progressive reloading of the musculoskeletal system, monitoring of nutritional parameters, and considerations for lactation.

EVIDENCE ACQUISITION

PubMed and CINAHL (Cumulative Index for Nursing and Allied Health Literature) were searched with the following search strategy: (extreme sports OR elite athletes OR running OR exercise) AND (breastfeeding OR lactation OR bone density OR fetal weight OR gestational weight gain OR postpartum or post-partum OR postnatal OR post-natal OR pregnancy OR childbirth). The following information is based on best available evidence and clinical experience.

STUDY DESIGN

Clinical review.

LEVEL OF EVIDENCE

Level 4.

RESULTS

Due to the interplay between cardiovascular fitness, postpartum nutrition, lactation, and progressive reloading of the muscular and skeletal system, we propose a multimodal, multidisciplinary approach to safely and successfully allow an athlete to return to an elite level of competition.

CONCLUSION

Return to running in the postpartum period is a highly individualized process that benefits from multidisciplinary, individualized care. This includes monitoring of nutrition, core and pelvic floor function, bone reloading, muscle and tendon reloading, and breastfeeding care when applicable.

STRENGH OF RECOMMENDATION TAXONOMY (SORT)

C.

A randomised interventional parallel study to evaluate the effect of different frequencies of pelvic floor muscle exercises with core stabilisation using three-dimensional ultrasound: the PELSTAB study

INTRODUCTION AND HYPOTHESIS

The primary objective was to compare high- and low-frequency pelvic floor muscle training (PFMT) with the impact on urinary incontinence episode frequency over 1 week (IEF/week). The secondary objective was to compare the two groups with regard to pelvic floor muscle function, morphometry, incontinence quality of life, and patient global impression.

METHODS

This was a randomised parallel controlled study. The setting was regional gynaecological and urological outpatient clinics. The subjects consisted of a sample of 86 women with stress urinary incontinence (SUI). Group A underwent high-frequency PFMT and group B underwent low-frequency PFMT for 12 weeks. We recorded the IEF/week. The International Consultation on Incontinence Questionnaire Urinary Incontinence Short Form (ICIQ-UI SF) was used. Pelvic floor muscle function was evaluated using a perineometer. Pelvic floor muscle morphometry was evaluated with 3D/4D ultrasound. The Urinary Incontinence Quality of Life Scale (I-QoL) was used.

RESULTS

Significant differences between group A and B after treatment (p<0.001) were noted in favour of group A in IEF/week (group A 10.2±7.0/2.3±3.0 vs group B 9.3±4.7/6.3±4.9), in the ICIQ-UI SF (group A 9.7±3.0/3.7 ± 3.6 vs group B 9.9±3.2/9.4±3.4). Significant differences between groups A and B after treatment were noted in favour of group A for pelvic floor muscle function in terms of maximal voluntary contraction and its duration, and also for pelvic floor muscle morphometry in terms of a reduction of the hiatal area during rest, contraction, and the Valsalva manoeuvre.

CONCLUSIONS

High-frequency PFMT for 12 weeks significantly decreased IEF/week in comparison with low-frequency PFMT. In the high-frequency exercise group, women had significantly better pelvic floor muscle function, morphometry and quality of life than the low-frequency exercise group.

Hiatal failure: effects of pregnancy, delivery, and pelvic floor disorders on level III factors

INTRODUCTION AND HYPOTHESIS

The failure of the levator hiatus (LH) and urogenital hiatus (UGH) to remain closed is not only associated with pelvic floor disorders, but also contributes to recurrence after surgical repair. Pregnancy and vaginal birth are key events affecting this closure. An understanding of normal and failed hiatal closure is necessary to understand, manage, and prevent pelvic floor disorders.

METHODS

This narrative review was conducted by applying the keywords "levator hiatus" OR "genital hiatus" OR "urogenital hiatus" in PubMed. Articles that reported hiatal size related to pelvic floor disorders and pregnancy were chosen. Weighted averages for hiatal size were calculated for each clinical situation.

RESULTS

Women with prolapse have a 22% and 30% larger LH area measured by ultrasound at rest and during Valsalva than parous women with normal support. Women with persistently enlarged UGH have 2-3 times higher postoperative failure rates after surgery for prolapse. During pregnancy, the LH area at Valsalva increases by 29% from the first to the third trimester in preparation for childbirth. The enlarged postpartum hiatus recovers over time, but does not return to nulliparous size after vaginal birth. Levator muscle injury during vaginal birth, especially forceps-assisted, is associated with increases in hiatal size; however, it only explains a portion of hiatus variation-the rest can be explained by pelvic muscle function and possibly injury to other level III structures.

CONCLUSIONS

Failed hiatal closure is strongly related to pelvic floor disorders. Vaginal birth and levator injury are primary factors affecting this important mechanism.

Postpartum pelvic floor muscle training, levator ani avulsion and levator hiatus area: a randomized trial

INTRODUCTION AND HYPOTHESIS

Vaginal delivery may lead to tearing of the levator ani (LA) muscle from its bony insertions (complete LA avulsion) and increased levator hiatus (LH) area, both risk factors for pelvic floor dysfunctions. Early active rehabilitation is standard treatment after musculo-skeletal injury. We hypothesized that pelvic floor muscle training (PFMT) early postpartum would reduce the presence of LA avulsions and reduce LH area.

METHODS

We carried out a planned secondary analysis from a randomized controlled study. Primiparous women (n=175) giving birth vaginally were included 6 weeks postpartum, stratified on complete LA avulsion, and thereafter randomized to PFMT or control. The training participants (n=87) attended a supervised PFMT class once a week and performed home-based PFMT daily for 16 weeks. The control participants (n=88) received no intervention. Presence of complete LA avulsion, LH area at rest, maximal contraction, and maximal Valsalva maneuver were assessed by transperineal ultrasound. Between-group comparisons were analyzed by analysis of covariance for continuous data, and relative risk (RR) for categorical data.

RESULTS

Six months postpartum, the number of women who had complete LA avulsion was reduced from 27 to 14 within the PFMT group (44% reduction) and from 28 to 17 within the control group (39% reduction). The between-group difference was not significant, RR 0.85 (95% CI 0.53 to 1.37). Further, no significant between-group differences were found for LH area at rest, during contraction, or Valsalva.

CONCLUSIONS

Supervised PFMT class combined with home exercise early postpartum did not reduce the presence of complete LA avulsion or LH area more than natural remission.

Predictive Value of Pelvic Floor Muscle Morphometry Using 3D/4D Ultrasound in Relation to the Success of Pelvic Floor Muscle Training in Women with Stress Urinary Incontinence

The aim of our study was to establish the predictive value of pelvic floor muscle morphometry using 3D/4D ultrasound in relation to the success of pelvic floor muscle training (PFMT) for 12 weeks in women with stress urinary incontinence (SUI). A total of 86 women with SUI from regional gynaecological and urological outpatient clinics were enrolled on this cross-sectional study. SUI symptoms were assessed by the International Consultation on Incontinence Questionnaire (ICIQ-UI SF). Pelvic floor muscle function was evaluated using a perineometer. Pelvic floor muscle morphometry (PFMM) was evaluated by the size of the urogenital hiatus (HA in cm²) at rest (R), at contraction (C) and during the Valsalva manoeuvre, i.e., a strong push (V), by 3D/4D USG. The intervention was PFMT for 12 weeks. After PFMT, we noted significant improvement in SUI symptoms, pelvic floor muscle function and morphometry. Moderately significant (0.001) negative correlations were confirmed between the total ICIQ-UI SF score and strength (-0.236 **) and endurance (-0.326 **) of the maximal voluntary contraction (MvC), the number of MvC lasting 3 s (-0.406 **) and 1 s (-0.338 **). Moderately significant (0.001) positive correlations were confirmed between the total ICIQ-UI SF score and R (r = 0.453 **), C (r = 0.533 **) and V (r = 0.442 **). The predictive value of PFMM reached a positive prediction of a decrease with an ICIQ-UI SF score below 8. HA during V was most strongly associated with SUI reduction, with an area under the curve (AUC) of 0.87 (p ≤ 0.001), a positive predictive value of 83.3%, a negative predictive value of 75.0%, sensitivity of 78.9% and specificity of 80.0%. The predictive values of pelvic floor muscle morphometry using 3D/4D USG confirmed the success of PFMT in women with SUI.

Effect of pelvic floor muscle training program in reducing postpartum levator hiatus area in Japanese women: A prospective cohort study using three-dimensional ultrasonography

AIM

To assess the effect of a pelvic floor muscle training (PFMT) program on postpartum levator hiatus area.

METHODS

A prospective cohort study was conducted at a clinic in Japan. Training and control groups were recruited from outpatient pregnant women at two separate time periods. Only the training group underwent the PFMT program, including education for home PFMT, home PFMT, and follow-up instructions. Education for home PFMT was held by 1 month postpartum to acquire the correct contraction of the pelvic floor muscle. Home PFMT was prescribed between 1 and 5 months postpartum; during this period, follow-up instructions were provided to keep the women motivated. Before and after home PFMT, the levator hiatus area was measured using ultrasonography.

RESULTS

In total, 44 women in the training group and 45 in the control group were analyzed. There were 36 women who reached a high adherence to three daily sets of home PFMT. The reduction in the levator hiatus area at rest was not statistically higher in the training group than that in the control group. For the subgroup with high adherence, the reduction in the area at rest was significantly higher by 4.43% in the training group than that in the control group (19.90% vs. 15.49%).

CONCLUSIONS

Although the PFMT program did not significantly reduce the postpartum levator hiatus area at rest, performing at least three sets of home PFMT each day significantly reduced the levator hiatus area by 4.43%.

CLINICAL TRIAL REGISTRATION

UMIN Clinical Trials Registry (ID; UMIN 000026188, Date; 17 February 2017).

[Changes in pelvic organ mobility and ligamentous laxity during pregnancy and postpartum. Review of literature and prospects]

INTRODUCTION

The role of pregnancy in pelvic floor disorders occurrence remains poorly known. It might exist a link between changes in ligamentous laxity and changes in pelvic organ mobility during this period. Our objective was to conduct a non-systematic review of literature about changes in pelvic organ mobility as well as in ligamentous laxity during pregnancy and postpartum.

METHODS

From the PubMed, Medline, Cochrane Library and Web of Science database we have selected works which pertains clinical assessment of pelvic organ mobility (pelvic organ prolapse quantification), ultrasound assessment of levator hiatus and urethral mobility, ligamentous laxity assessment during pregnancy and postpartum.

RESULTS

Clinical assessments performed in these works show an increase of pelvic organ mobility and perineal distension during pregnancy followed by a recovery phase during postpartum. Pelvic floor imaging shows an increase of levator hiatus area and urethral mobility during pregnancy then a recovery phase in postpartum. Different authors also report an increase of ligamentous laxity (upper and lower limbs) during pregnancy followed by a decrease phase in postpartum.

CONCLUSION

Pelvic organ mobility, ligamentous laxity, levator hiatus and urethral mobility change in a similarly way during pregnancy (increase of mobility or distension) and postpartum (recovery).

LEVEL OF EVIDENCE

3.

Variability of the pubic arch architecture and its influence on the minimal levator hiatus area

OBJECTIVE

To investigate the association between the minimal levator hiatus (MLH) area at rest with its surrounding soft-tissue and bony structures in nulliparous asymptomatic women with a normal levator ani muscle.

METHODS

A subanalysis was undertaken of a prospective study of the appearance of the levator ani in asymptomatic nulliparous women conducted between September 2010 and September 2011. The subanalysis included women with a normal levator ani muscle. Three-dimensional ultrasonography volumes were used to obtain pelvic floor measurements.

RESULTS

The analysis included 56 women with mean age of 43.0±13.4years. The mean MLH area was 13.1±1.8cm(2) (range 9.0-17.3). The pubic arch angle had no influence on the MLH area (Pearson correlation coefficient r=0.13). Height and pubic arch length were positively correlated with the MLH area (r=0.26 [P=0.52] and r=0.50 [P<0.001], respectively).

CONCLUSION

The MLH size of nulliparous women varied widely and was positively correlated with the height and pubic arch length of the women. Therefore, caution is warranted when interpreting the MLH area as an indicator of a levator ani defect or a predictor of pelvic organ prolapse without taking a woman's pelvic bone characteristics into account.

Pregnancy-induced adaptations in the intrinsic structure of rat pelvic floor muscles

OBJECTIVE

Maternal birth trauma to the pelvic floor muscles (PFMs) is a major risk factor for pelvic floor disorders. Modeling and imaging studies suggest that demands placed on PFMs during childbirth exceed their physiologic limits; however many parous women do not sustain PFM injury. Here we determine whether pregnancy induces adaptations in PFM architecture, the strongest predictor of muscle function, and/or intramuscular extracellular matrix (ECM), responsible for load bearing. To establish if parallel changes occur in muscles outside of the PFM, we also examined a hind limb muscle.

STUDY DESIGN

Coccygeus, iliocaudalis, pubocaudalis, and tibialis anterior of 3-month-old Sprague-Dawley virgin, mid-pregnant, and late-pregnant; 6-month-old virgin; and 4- and 12-week postpartum rats (N = 10/group) were fixed in situ and harvested. Major architectural parameters determining muscle's excursion and force-generating capacity were quantified, namely, normalized fiber length (Lfn), physiologic cross-sectional area, and sarcomere length. Hydroxyproline content was used as a surrogate for intramuscular ECM quantity. Analyses were performed by 2-way analysis of variance with Tukey post hoc testing at a significance level of .05.

RESULTS

Pregnancy induced a significant increase in Lfn in all PFMs by the end of gestation relative to virgin controls. Fibers were elongated by 37% in coccygeus (P < .0001), and by 21% in iliocaudalis and pubocaudalis (P < .0001). Importantly, no Lfn change was observed in the tibialis anterior. Physiologic cross-sectional area and sarcomere length were not affected by pregnancy. By 12 weeks' postpartum, Lfn of all PFMs returned to the prepregnancy values. Relative to virgin controls, ECM increased by 140% in coccygeus, 52% in iliocaudalis, and 75% in pubocaudalis in late-pregnant group, but remained unchanged across time in the tibialis anterior. Postpartum, ECM collagen content returned to prepregnancy levels in iliocaudalis and pubocaudalis, but continued to be significantly elevated in coccygeus (P < .0001).

CONCLUSION

This study demonstrates that pregnancy induces unique adaptations in the structure of the PFMs, which adjust their architectural design by adding sarcomeres in series to increase fiber length as well as mounting a substantial synthesis of collagen in intramuscular ECM.

The levator ani muscle during pregnancy and major levator ani muscle defects diagnosed postpartum: a three- and four-dimensional transperineal ultrasound study

OBJECTIVE

To investigate associations between levator hiatus area and levator ani muscle function during pregnancy and major levator ani muscle defects postpartum.

DESIGN

Observational prospective cohort study.

SETTING

University hospital, Norway.

SAMPLE

A cohort of 234 nulliparous women at 21 and 37 weeks of gestation, and at 6 weeks postpartum.

METHODS

Ultrasound measurements of the levator hiatus at rest, during pelvic floor muscle contraction, and during the Valsalva manoeuvre were taken at 21 and 37 weeks of gestation. Levator ani muscle function was estimated as the percentage changes in levator ani muscle length from rest to contraction, and the level of muscle stretch during the Valsalva manoeuvre. Major levator ani muscle defects were diagnosed at 6 weeks postpartum using tomographic ultrasound imaging.

MAIN OUTCOME MEASURES

Associations between ultrasound measurements antepartum and major levator ani muscle defects postpartum.

RESULTS

Women with major levator ani muscle defects postpartum had significantly smaller levator hiatus area at rest and during the Valsalva manoeuvre at mid-pregnancy (mean difference 1.03 cm(2) , 95% CI 0.31-1.76; 2.92 cm(2) , 95% CI 1.77-4.07), and at 37 weeks of gestation (mean difference 1.47 cm(2) , 95% CI 0.62-2.32; 2.84 cm(2) , 95% CI 0.88-4.80), than women without such defects. They also had significantly less shortening of the levator ani muscle during contraction at 37 weeks of gestation.

CONCLUSIONS

Smaller levator hiatus area at rest and during the Valsalva manoeuvre at mid and late pregnancy, and less shortening of the levator ani muscle during contraction at 37 weeks of gestation, are associated with major levator ani muscle defects postpartum.