Pelvic-Floor Dysfunction Prevention in Prepartum and Postpartum Periods

Every woman needs to know about the importance of the function of pelvic-floor muscles and pelvic organ prolapse prevention, especially pregnant women because parity and labor are the factors which have the biggest influence on having pelvic organ prolapse in the future. In this article, we searched for methods of training and rehabilitation in prepartum and postpartum periods and their effectiveness. The search for publications in English was made in two databases during the period from August 2020 to October 2020 in Cochrane Library and PubMed. 77 articles were left in total after selection—9 systematic reviews and 68 clinical trials. Existing full-text papers were reviewed after this selection. Unfinished randomized clinical trials, those which were designed as strategies for national health systems, and those which were not pelvic-floor muscle-training-specified were excluded after this step. Most trials were high to moderate overall risk of bias. Many of reviews had low quality of evidence. Despite clinical heterogeneity among the clinical trials, pelvic-floor muscle training shows promising results. Most of the studies demonstrate the positive effect of pelvic-floor muscle training in prepartum and postpartum periods on pelvic-floor dysfunction prevention, in particular in urinary incontinence symptoms. However more high-quality, standardized, long-follow-up-period studies are needed.


Introduction
Pelvic organ prolapse (POP) affects about 50% of women undergoing routine gynecological examination [1]. It is a common condition among parous women and has negative effect on the quality of life in general and especially affecting sexual life and self-confidence. The amount of POP is likely to increase in the future. It is thought that in 2050 the number of women with POP in the USA will increase by about 46% [2].
Main POP risk factors are parity, advancing age, obesity, and others-race and ethnicity, collagen abnormalities, hysterectomy, elevated intraabdominal pressure, and family history [3][4][5][6][7][8][9][10]. Most of the POP risk factors are unchangeable, which emphasizes the role of POP prevention. Even though the incidence of POP increases with age, women at young age should start intervening to prevent this condition from happening in the future [3,5,9]. Every woman needs to know about the importance of the function of pelvic-floor muscles (PFM) and POP prevention, especially pregnant women since parity and labor are the factors which have the biggest influence on having POP in the future [3,4,9,11]. Compared to natural delivery, Cesarean delivery mode is not completely protective [12]. There are other health problems such as urinary incontinence (UI), anal incontinence (AI), or sexual disfunction which usually goes with POP and has similar risk factors and etiology. POP is one of the most common diagnoses composing pelvic-floor dysfunction (PFD). According to the International Urogynecological Association (IUGA) and the International Continence Society (ICS), who made a joint report on the terminology for Female Pelvic-Floor Dysfunction, PFD is a wider term covering the following diagnosis: POP, urodynamic stress were excluded, for example: "general fitness classes in pregnancy effect on postpartum period" (Figure 1). Most of the clinical trials were studies of intervention group (for example: PFMT supervised by specialist, PFMT using various rehabilitation devices) versus control group (for example: PFMT at home, no PFMT) in pregnant and postpartum women, most of them were analyzed by intention-to-treat principle. Randomized clinical trials (RCT) were grouped by the symptoms they treated (Table 1). For assessing risk of bias, RoB 2 tool was used in RCTs. Most of the trials were unclear risk of selection bias because of insufficient information provided on random sequence generation and high to moderate overall risk, due to low numbers of participants, participants, and personnel blinding errors, and short follow-up terms. far-infrared radiation (FIR) effectiveness on perineal pain and sexual function (SF) improvement postpartum.
no additional benefit of postpartum FIR on primiparous women undergoing an episiotomy and 2nd degree perineal lacerations.
p > 0.05 there was no statistically significant differences between groups. PFMT effect on desire, pain, lubrication, orgasm, female sexual index (FSFI) scores, pelvic-floor muscle strenght 4th and 7th month postpartum.
All domains, except satisfaction, were significantly higher in the training group compared with the controls. Pelvic-floor-muscle strength was found to be increased in the 7th month in the training group.
p < 0.001 sexual arousal, lubrication, orgasm, and satisfaction scores were improved in the 7th month in the training group p < 0.001 Pelvic-floor-muscle strength was found to be increased in the 7th month in the training group Control group vs. intervention group: assessment by nurses of UI with conservative advice on PFMT at 5, 7, and 9 months after delivery supplemented with bladder training at 7 and 9 months.
Signifficant improvement on UI in intervention group. Fecal incontinence was also less common in intervention group. Women in intervention group were more likely to still perform PFMT  Intervention group: daily perineal massage and pelvic-floor exercises from 32 weeks of pregnancy Vs standart care.
There was a significant reduction in episiotomy rates in intervention group, also less III-IV degree tears, less postpartum perineal pain.
no added value in using early home biofeedback physiotherapy in the management of women sustaining third-degree tears. There was no significant difference in anal resting and squeeze pressure values and in symptom score and quality of life measurements between the groups. anal resting and squeeze pressure values p = 0.123 and p = 0.68 Long-term effect of a postpartum PFMT course in prevention and treatment of UI.
PFMT course was effective in the prevention and treatment of stress UI. At the 1 year follow-up, significantly more women in control group than in the training group reported stress UI/or showed urinary leakage at the pad test.
Difference between control and intervention group (UI and pad test) p < 0.01. The prevalence of incontinence was significantly less in the intervention group than in the control group. There were no significant differences between the groups as regards perineometry measurements or pad test results.
The prevalence of incontinence p = 0.0003

PFMT and Sexual Life Quality
PFMT effect on women's sexual life was analyzed in 7 RCTs. All the RCTs analyzed the postpartum period. Only 4 RCTs used questionnaires or scales to evaluate sexual function (SF): Marinoff Dyspareunia Scale, female sexual index (FSFI), sexual self-efficacy questionnaire, International consultation on incontinence (ICIQ) modular questionnairevaginal symptoms (ICIQ-VS), and ICIQ sexual matters module ICIQ-FLUTSsex. There was a tendency of improvement in SF postpartum by doing PFMT or PFMT combined with intravaginal transcutaneous electrical nerve stimulation (TENS), there was improvement in vaginal laxity, arousal, lubrication, orgasm, and dyspareunia, no evidence of improvement found of using far-infrared radiation (FIR) device. There was an improvement in desire and pain symptoms in control group (no PFMT) within a 3-month period from the 4th to 7th month postpartum in one trial, but another trial showed improvement in pain symptoms with intensive PFMT, where both trials used FSFI questionnaires [17,18]. There were no major differences in vaginal symptoms between PFMT and control groups in one trial, but the PFMT group showed improvement in vaginal laxity symptoms, especially when there were levator ani muscle defects [17]. There is only low quality of evidence due to small sample sizes, short follow-up, randomization and blinding errors, and lack of standardized training reporting [19][20][21][22][23][24][25][26].

PFMT and Pelvic-Floor Dysfunction
A mix of symptoms-POP, UI, and AI-were analyzed in 10 RCTs. Most of the RCTs trained women during the postpartum period. There were PFMT used together with rehabilitation devices such as: Direct Vagina Low Voltage Low Frequency Electric Stimulation (DES), transvaginal electrical stimulation (TVES), EMG-triggered neuromuscular stimulation, electrical stimulation (ES) with biofeedback treatment, sacral neuromodulation, bipolar vaginal radiofrequency device (VotivaTM, InMode), EmbaGYN, Magic Kegel Master devices. Other treatment procedures included injections of collagen. In addition, there was classical PFMT versus control group RCTs. ES with biofeedback and DES showed promising results in decreasing POP symptoms. In one trial, a group of patients, whose POP and UI symptoms improved the most, and started PFMT very early second day postpartum, regardless of whether they had episiotomy or second-degree perineum laceration, they received DES therapy 6 weeks postpartum [25]. TVES showed no evidence of improvement in PFD questionnaires or muscle strength, but there was a higher rate of correct PFM contraction in the group with weak PFM, which received TVES 5 times in 7 to 14 weeks postpartum [27]. Sacral neuromodulation showed improvement in AI, UI, and life-quality symptoms. Vaginal radiofrequency devices showed no evidence of improvement in POP, UI, or AI symptoms. EmbaGYN and Magic Kegel Master devices showed significant improvement in UI symptoms. Three PFMT versus control group RCTs showed no significant improvement in any of symptoms. One RCT with a high sample size and long follow-up showed promising results in UI symptoms, but the effect did not last for 12 months (Glazener C M 2001 and. PFMT together with rehabilitation devices may improve PFD symptoms, but the results should be evaluated with care, due to small samples, selective reporting, and selection and performance biases.
One RCT analyzed PFMT effect in postnatal AI treatment. There was a significant difference in the reduction of St. Mark's scores in favor of PFMT.

PFMT and Obstetrical Injuries
Three RCTs analyzed various techniques to avoid obstetrical injury and/or episiotomy. Two RCTs analyzed antenatal use of Epi No device; neither found significantly lower incidence of anal sphincter, levator ani muscle injury or episiotomy in the Epi No group. One RCT compared antenatal perineal massage with PFMT to standard care. There was a significant reduction in episiotomy rates in the intervention group, also less third-to fourth-degree tears and less postpartum perineal pain. Two RCTs analyzed postpartum PFMT, one when there was an obstetrical anal sphincter injury (OASIS) and another when there was third-degree tears. None of them found statistically significant improvement after intervention [37][38][39][40][41].

PFMT and UI Prevention and Treatment
The highest number of RCTs-22-analyzed prepartum and/or postpartum PFMT effect on UI. To evaluate the effect of PFMT, six of them used specialized questionnaires: International Consultation on Incontinence Questionnaire Overactive Bladder (ICIQ-OAB), Urogenital Distress Inventory (UDI), Incontinence Impact Questionnaire (IIQ), International Consultation on Incontinence Questionnaire-short form (ICIQ-UI SF), International Consultation on Incontinence Questionnaire Lower Urinary Tract Symptoms Quality of Life Module (ICIQ-LUTSqol), and in most of them there was a statistically significant difference in favor of PFMT. Five used self-reported symptoms of UI. Two RCTs used Pad test to evaluate UI, one used bladder neck mobility. Most of the trials showed the positive effect of PFMT on UI, and PFMT group had less UI events in late pregnancy. One trial showed that written instructions of how to perform PFMT gives similar result as PFMT with specialist follow-up. Three trials showed the great effect of combined rehabilitation methods, e.g., PFMT with ES. Positive PFMT together with ES had long-lasting effect on UI; follow-up one year after intervention was conducted in one trial [42]. Preventative PFMT effect on UI was still present after 7 years in one trial [43]. One big sample (723 patients recruited, 234 included in trial) trial found that PFMT was non-effective in preventing future incontinence [44]. Only three RCTs followed up women after more than 6 months .

Systematic Reviews about Antenatal and Postnatal PFMT
Systematic review characteristics are shown in Table 2. For assessing quality of evidence, the GRADE tool was used in systematic reviews. Many of the reviews were downgraded to low or very low quality of evidence, due to small samples of RCTs, low evidence quality of RCTs, high heterogeneity, and selective reporting biases. The main systematic review, which is continuous and is regularly updated and provides the highest level of evidence is Woodley et al. in Cochrane Systematic Review. The main conclusions from the reviews were that there is a lack of high-quality randomized and standardized studies. It is very hard to avoid randomization bias in PFMT-based interventions, due to difficulties of blinding. Despite clinical heterogeneity among the RCTs, PFMT shows promising results in reducing UI and improving quality of life, SF, and AI scores after pregnancy [64][65][66][67][68][69][70][71][72].

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Evidence showed that PFMT in primi or multi-parous women can boost SF in postpartum and it is a safe strategy. The review of these studies has some implications for practice. It has been suggested that postpartum women who do PFMT may benefit from this procedure, increasing sexual health and QoL. Therefore, health professionals should encourage women to do postnatal exercise.
⊕⊕ LOW Due to high risk of bias and small sample sizes

Discussion
Most of the studies agree with the use of PFMT in PFD prevention in prepartum and postpartum periods, although more high-quality studies are needed.
Good results are demonstrated by using biofeedback therapy, which allows patients to see and evaluate their progress. Studies which have used biofeedback training also had longer follow-up period from 6 months to 7 years [26,43,53].
Higher-quality studies are needed to investigate SF. Higher sample sizes, randomization of participants, and at least 3 to 12 months of follow-up is needed. No results of SF in prepartum period are known, although this period is hard to evaluate because of physical and psychological changes in women. PFMT improves muscle mass and tone, which is the opposite for looseness or laxity. PFMT helps to reach targeted results if patients experience symptoms such as "vagina feels loose or lax" [21]. If patients experience dyspareunia symptoms, additional effects could be reached by adding TENS to the PFMT program [22]. Some of the symptoms may improve within the time after delivery without PFMT, but PFMT groups in most of the trials reached improvement in greater variety of symptoms. Also, PFMT effectively improved SF when there were muscle defects, and intensive PFMT may help to reduce pain during intercourse and painful perineal scar formation [17,18].
Higher-quality evidence is needed about rehabilitation device (ES, TVES, FIR, sacral neuromodulation, radiofrequency, Kegel trainers) usage to treat prepartum and postpartum PFD. ES may be useful to relieve pain and muscle hypertonus; in this way it may improve dyspareunia symptoms. ES and TVES may be not that effective in improving muscle mass and tonus but it may help to teach patients with extremely weak perineal muscles how to perform a correct PFM contraction [20,27].
Kegel training devices may improve PFD symptoms and increase muscle tone; it is comfortable for patients, because they can use the devices at home, but there is a lack of strong scientific evidence. Usage of the device should be precisely documented, which is hard when patients are training at home all by themselves, therefore training time and number and strength of contractions and other parameters important for device effect evaluation may be poorly documented and not suitable to compare between study participants [33]. The Epi No device does not significantly reduce perineal trauma and episiotomy rates. Perineal massage and PFMT may give promising results in reducing perineal tears and episiotomy rates, but more high-quality studies with well documented technique and study protocols are needed to evaluate perineal muscle relaxation techniques' additional effects in avoiding perineal trauma [37][38][39][40][41].
There are established results that antenatal PFMT helps to prevent UI in late pregnancy and reduce UI rates after delivery. Preventative PFMT effect is long-lasting. The best results are in continent women when they start structured PFMT at early pregnancy. The highest numbers of studies evaluate this symptom and here we have highest quality of evidence. Both antenatal and postnatal PFMT may improve quality of life, reduce urogenital distress and urinary symptoms after delivery [45,46,66,70]. Patients should get at least written instructions how to do PFMT. There is a big variety of questionnaires and methods used to evaluate UI symptoms in RCTs; less than a half of analyzed trials used certified questionnaires. Also, follow-up time after intervention was relatively short. Only a few trials followed patients longer than half a year. More standardized, high sample and longer follow-up studies are needed [66].
Too few trials analyzed PFMT effect on AI and POP prevention. More studies are needed in this field. Late pregnancy is associated not only with higher incidence of UI, but also AI and involuntary loss of flatus. External anal sphincter muscle might be trained the same way as other perineal muscles. Most studies evaluating PFD lack data about involuntary loss of flatus or stool during late pregnancy and postpartum and PFMT effect on this condition. POP reduction in RCT control groups shows that regeneration after delivery improves this condition even without PFMT in a short period (6 weeks to 1 year after delivery), but what is still unclear is whether there a difference between PFMT groups and control groups after a longer time [29][30][31][32][33][34][35][36]43]. Pelvic-floor rehabilitation including various rehabilitation methods and PFMT is recommended as a POP treatment, and there were more severe degrees of POP prevention method in middleaged women with asymptomatic or mildly symptomatic minor degree POP [73,74]. One of the reasons-that analyzed trials and reviews cannot provide strong evidence of the use of PFMT in POP prevention-might be that there is an increase in intensity of physical activity and weight-lifting in the postpartum period, due to returning to pre-pregnancy lifestyle and additionally baby-care routine which includes baby and baby-stroller lifting. These activities, if performed incorrectly, may increase severity of POP [36,75]. Other possible reason is follow-up period; if patients start training about 6 weeks postpartum and the last follow-up point is 6 months postpartum, the time interval is too short to evaluate the preventative effect of PFMT. There is also a lack of studies with PFMT and perineal rehabilitation timing; according to one trial, there might be a positive effect in POP prevention when PFMT is started very early-second day after delivery-regarding the episiotomy or perineal lacerations [25][26][27][28][29][30][31][32][33][34][35][36]74].
Proposals for research: there is high heterogeneity in RCTs. It is recommended to use more standardized measures-approved questionnaires to evaluate symptoms, use of validated terminology, for example joint IUGA-ICS terminology reports, PFMT reporting, for example use of a Consensus on Exercise reporting template, more attention to antenatal exercises effects, and longer follow-up [15,66]. Still, more evidence is needed about the best timing of PFMT in the postpartum period [25]. There are also some methods that were useful in treating middle-aged women with UI or POP symptoms; however, their effect on prepartum and postpartum women is unknown, for example extracorporeal magnetotherapy [76].
Proposals for practice: prepartum patient counseling about pelvic-floor anatomy and functions and how to prevent PFD during pregnancy and after labor is a necessary point of PFD prevention. Women should be encouraged to perform PFMT in prepartum and postpartum periods, because of the proven positive effect on UI prevention and treatment. National strategies for pregnancy and postpartum PFR programs orientated to PFD prevention should be a priority in national healthcare systems due to the high prevalence of POP and UI and the prediction for them to increase in general female population [2,11,16,66].

Study Limitations
This study had some limitations: limited number of databases used for literature search; article language was only English; short period of time for article selection; reporting bias due to selective reporting; and exclusion of incomplete articles.
This study did not receive any funding. The authors of the review declare no conflict of interests.