Weakness of the pelvic floor muscles (PFM) is a disease based on the loss of function of the pelvic muscles due to trauma during childbirth, surgery, and aging. If this condition is untreated - the pathology can progresses to genital prolapse. The manifestations of the disease noted from 2.9% to 53% of women, but the real prevalence is unknown. In this regard, weakness of PFM requires early diagnosis and timely conservative treatment. The aim of study – to improve treatment outcomes for women of reproductive age with weakness of PFM.

A prospective randomized, open-label, comparative study. 135 women were examined. All variables were checked for normality by the Kolmogorov-Smirnov test. Descriptive statistics were estimated by the sample mean with 95% confidence interval. The differences between groups were tested using analysis of variance test followed by Least Significant Difference post hoc tests. Levene’s test of homogeneity of variance was run before analysis of variance to verify the equal variances in groups. Paired variables were tested by a student’s t-test. All statistical tests were 2-tailed. Whole statistical analysis was conducted with Statistica v.6 (StatSoft Inc, Tulsa, OK), and the significance level was set as default to 0.05 (5%). Initially, the minimum sample size was verified by using Statistica software. At least 19 subjects must have been included in each of the 3 tested groups, to achieve a power of 80% with a ¼ 5%. Inclusion criteria: age  of patients 18-45 years; history of vaginal childbirth (not earlier than 6 months ago); weakness of PFM, genital prolapse of the 1 stage by POP-Q. Exclusion criteria: pregnancy at the time of therapy initiation; genital prolapse II-IV stage by POP-Q; indications for surgical treatment; general contraindications for physiotherapy. All the patients signed a voluntary informed consent. Patients who showed PFMs weakness and continence issues received energy-based therapy. The main group (n = 50) received high-intensity focused electromagnetic (HIFEM) therapy with the BTL EMSELLA (BTL Industries Inc, Boston, MA). The comparison group (n = 48) received low-frequency stimulation of the pelvic floor muscles using the BioBravo (MTR+ Vertriebs GmbH, Germany) device at home. The average age of the patients was 34.07 ± 6.37 years. The control group  (group III) consisted of 37 women who had history of vaginal childbirth without signs of PFMs weakness. All patients before therapy, after it and after six months underwent analysis of medical history, general and gynecological examination with palpation of the pelvic floor muscles strength, 3D transperineal ultrasound of the pelvic floor area by Voluson E10 device (RIC6-12-D transducer), surface EMG research on Myomed 632 (Enraf-Nonius B.V., Netherlands) , questionnaires. To study the electrogenesis and changes in baseline tone and endurance of the pelvic floor muscles, gluteal muscles, and muscles of the anterior abdominal wall, 2 types of superficial electrodes were used: first was applied on the anterior abdominal area (served as reference), and the second (vaginal) electrode was mounted on the intravaginal probe. Registration of muscle potential with the electrodes on anterior abdominal area made it possible to differentiate contractions and avoid an increase in intra-abdominal pressure and the involvement of synergistic muscles when performing special exercises. Myofeedback was displayed on the device’s monitor unit. All patients were instructed of the correct stereotype of contractions of the pelvic floor muscles without other groups of muscles.

The most frequent complaints of PFMs weakness were revealed: decreased sensitivity in intimacy - 61.33%; vaginal noise - 57.33%; hypo / anorgasmia - 48%; sensation of wide vagina - 46.67%. In 73.33% of cases was observed the urinary incontinence. Sonographic signs of structural and functional changes in the pelvic floor in patients with PFMs weakness in comparison (p <0.05) with the control group are: an increase in the ureterovesical angle by 1.5 and 2.0 times (at rest 25.68 ° ± 7.81 ° versus 17.00 ° ± 4.45 ° and with straining 48.79 ° ± 11.04 ° versus 25.41 ° ± 5.23 °); an increase in the anteroposterior and laterolateral diameter of levator hiatus  1.1 and 1.3 times (51.85 ± 6.31 mm versus 46.57 ± 2.32 mm and 44.07 ± 6.97 mm versus 35.43 ± 2 , 52 mm), decrease in thickness m. puborectalis by 1.2 and 1.3 times (on the right 5.15 ± 1.58 mm versus 6.35 ± 0.50 mm and on the left 5.44 ± 1.57 mm versus 6.31 ± 0.69 mm) without violations of the avulsion of the fascia. The patients of the studied cohort are distinguished by a lower contractility of the pelvic floor muscles (p <0.05), verified by electromyography. The significant (p <0.05) decrease in the average contraction of the pelvic floor muscles by 2.7 times (12.19 ± 5.65 mV versus 32.73 ± 3.96 mV) and a decrease in the retention time of the contraction by 2.7 times (23.14 ± 12.43 seconds versus 61.76 ± 7.75 seconds). In order to assess the integrity of the pelvic floor fascia by ultrasound, the levator-urethral gap did not differ in healthy women and women suffering from PFMs weakness (<25 mm).

In group I, after the therapy, in contrast to group II, the percentage of complaints significantly decreased. Verbal communication analysis showed a statistically significant improvement in both groups according to the results of the questionnaires. However, the main group performed better results. According to the PFDI-20 questionnaire, in group II the final change was 2.6 times less than in group I, and PFIQ-7 and ICIQ-SF showed the result of the main group, exceeding the comparison group by 3 and 2.8 times, respectively. The I-QOL questionnaire showed a significant improvement in the quality of life, more pronounced in group I. The 3D transperineal ultrasound showed statistically significant changes in both groups with a predominance of positive dynamics in group I. The amount by which the ureterovesical angle at rest decreased is almost 3 times greater than in the group II, and its value is similar to that in group III. When straining, the ureterovesical angle in the main group decreased by 12.42°, while in the comparison group this indicator was only 2.25. Changes in the size of the levator hiatus in group I were also statistically significantly greater than in group II: the anteroposterior diameter decreased by 3.12, the laterolateral diameter  by 3.04; in the comparison group, these indicators are 1.21 and 1.1, respectively. Results of electromyographic study: the maximum and average contractions in the main group increased by 1.5 times and were close to those of the control group, while the comparison group showed an improvement only by 1.08 and 1.07 times, respectively. The retention time of muscle contraction in group I also increased 1.5 times. Group II showed an increase in this parameter by 1.35 times. At the control examination of patients six months later, the results of therapy in group I were preserved, while in group II there was a deterioration of the studied parameters.

Conservative therapy at an early stage in the development of PFMs weakness can improve the quality of women`s life, as well as prevent the development of genital prolapse. In the treatment of PFMs weakness inducted PFM strengthening has been shown the highly effect. Based on the data obtained, HIFEM therapy has shown greater efficiency in comparison with electrical stimulation of the pelvic floor muscles.