ORIGINAL ARTICLE 847 Key words: Muscle Strength; Pelvic Floor; Sexual Behavior; Parity Int Braz J Urol. 2013; 39: 847-52 __________________ Submitted for publication: March 11, 2013 __________________ Accepted after revision: September 16, 2013 Objective: The aim of this study was to assess pelvic floor muscle (PFM) strength in diffe- rent body positions in nulliparous healthy women and its correlation with sexual activity. Materials and Methods: Fifty healthy nulliparous women with mean age of 23 years were prospectively studied. Subjective evaluation of PFM was assessed by transvaginal digital palpation (TDP) of anterior and posterior areas regarding the vaginal introitus. A perineometer with inflatable vaginal probe was used to assess the PFM strength in four different positions: supine with extended lower limbs (P1); bent-knee supine (P2); sitting (P3); standing (P4). Results: Physical activity, 3 times per week, was reported by 58% of volunteers. Sexual activity was observed in 80% of women and 82% of them presented orgasm. The average body mass index (BMI) was 21.76 kg/m2, considered as normal according World Health Organization (WHO). We observed that 68% of volunteers were conscious about the PFM contraction. TDP showed concordance of 76% when anterior and posterior areas were compared (p = 0.00014). There was not correlation between PFM strength and orgasm in subjective evaluation. The PFM strength was significantly higher in standing position when compared with the other positions (p < 0.000). No statistical difference was obser- ved between orgasm and PFM strength when objective evaluations were performed. Conclusions: There was concordance between anterior and posterior areas in 76% of cases when subjective PFM strength was assessed. In objective evaluation, higher PFM strength was observed when volunteers were standing. No statistical correlation was ob- served between PFM strength and orgasm in nulliparous healthy women. Pelvic floor muscle strength evaluation in different body positions in nulliparous healthy women and its correlation with sexual activity _______________________________________________ Mônica Orsi Gameiro, Luciana Miraglia, Luiz Felipe Orsi Gameiro, Carlos Roberto Padovani, João Luiz Amaro Physiotherapy Service (MOG, LM, LFOG); Department of Biostatistics (CRP) and Department of Urology (JLA) School of Medicine, São Paulo State University, Botucatu, SP, Brazil ABSTRACT ARTICLE INFO_________________________________________________________ ___________________ INTRODUCTION The vagina and bladder are correlated to the pelvic floor muscles (PFM), comprising the elevator ani and puborectalis. Likewise, decrease of pelvic floor muscle (PFM) strength in women may cause urinary incontinence (UI) (1) or sexual disorders (2). The recovery of these muscles could be therapeutic (3,4). On the other hand, Dietz et al. (5), studying nulliparous women, reported that pelvic floor musculature was strongly required during sexual intercourse, and increased elevator activity was also observed. These facts suggest a possible correlation between sexual activity and doi: 10.1590/S1677-5538.IBJU.2013.06.11 Vol. 39 (6): 847-852, November - December, 2013 IBJU | pelvic floor Muscle strength and correlation with sexual activity 848 stronger pelvic floor muscle. Some studies report a relationship between women’s sensation du- ring sexual intercourse as well as the vaginal grip intensity felt by their partner (6,7). Puborectalis muscle may play an important role in the cons- trictor function of PFM. Thus, its assessment, by vaginal pressure measurement, could be a deter- minant factor for PFM evaluation (8,9). Some authors have advocated different forms of PFM assessment using tools such as ul- trasound (10), electromyography (EMG) (11) and magnetic resonance imaging (MRI) (12). These different approaches may also permit to evaluate other aspects of PFM activity when compared with vaginal squeeze pressure. Another important point would be women’s body position during pelvic floor evalu- ation. Another study observed that digital muscle testing and vaginal pressures using manometry are reliable tools for measuring maximum volun- tary contraction in supine and upright positions (13). However, there is no consensus on the best form to evaluate the PFM strength as well as its baseline concerning nulliparous healthy women and its relationship with sexual activities. Thus, we propose to assess PFM strength in different body positions and also to evaluate its correlation with sexual activity in this specific population. MATERIALS AND METHODS From March to September 2006, fifty he- althy nulliparous volunteers of healthy area were recruited by an invitation letter. Mean age was 23 years old (range 20-30). The group comprised women with higher education level (University). This study was approved by the “Ethical Resear- ch Committee” (protocol n.368/2005). All parti- cipants were informed about its importance and signed the “Free Informed Consent”. Exclusion criteria were UI or urinary com- plaints, neurological diseases, previous pelvic sur- geries, diabetes, smoking and cognitive problems. Women were evaluated through a clini- cal questionnaire. Sexual activity was assessed by self-applicable anonymous questionnaire, compo- sed of two simples questions: 1 - Have you had sexual intercourse in the last 3 months? Yes/ No; 2 - Did you have orgasm during this intercourse? Yes/ No. BMI was calculated and classified accor- ding to the World Health Organization (WHO) (14). Subjective and objective PFM evaluations were performed in all women. For the subjective evaluation, volunteers were placed in supine position, undressed from waist to feet, covered with a sheet with the lower limbs bent and separated and instructed about the correct PFM contraction. They were evaluated by only one examiner through transvaginal digital palpation (TDP) of anterior and posterior areas regarding the vaginal introitus (Figure-1); they were also required to contract the perineal mus- cles and hold this contraction as long as possible. The classification of the PFM strength contraction Figure 1 - Bidigital vaginal palpation regarding the vaginal introitus. (A) anterior and (B) posterior areas. A B IBJU | pelvic floor Muscle strength and correlation with sexual activity 849 was performed according to the description of Ama- ro et al. (4), that it has been tested but not validated. The objective measurement was obtained with a Dynamed portable perineometer (model DM01), in four different patient positions (Figure-2): supine with lower limbs extended (P1); bent-knee lying (P2), sitting (P3), and standing (P4). When the participants were in position, examiner introduced a balloon catheter, sized 11 x 2.6 cm, into the va- gina. The balloon catheter was covered with a non- -lubricated condom, and filled with 60 mL of air permitting contact with the vaginal wall. This value was standardized at 60 mL in all participants. The equipment was immediately zeroed, three PFM con- tractions were requested and held as long as possi- ble with nearly 30-second of rest interval between each one. Maximal peak of each contraction was registered in cmH2O. The length of time of these contractions was recorded in seconds with chrono- meter. The average of three measurements was used to avoid biased results. Statistical analysis Qualitative variables were analyzed using the proportion test of concordances (15). Mann- -Whitney Test was used for comparisons between PFM strength and the presence or not of orgasm. For the comparison of PFM strength in different body positions, the Friedman’s non-parametric test was used and complemented by the Dunn multiple comparison tests. For comparing the time of PFM contractions, the technique of variance analysis for measurements of repeated models was used and complemented by Bonferroni’s test (16). Statistical analysis was performed at 5% of significance level. RESULTS The mean age of women’s menarche was 12 years old. Sexual activity was reported by 80% and 82% of these women reported orgasm. Regular physical activity, at least three times a week, was Figure 2 - Pelvic floor muscle assessment using manometry testing in four different positions. P1: supine. P2: Bent-knee lying. P3: Sitting. P4: Standing. IBJU | pelvic floor Muscle strength and correlation with sexual activity 850 reported by 58% of volunteers and 54% of them presented symptoms of constipation. Average BMI was 21.76 Kg/m2, considered as normal according to WHO. PFM subjective evaluation showed that 68% of women were conscious of musculature contraction. The TDP in anterior position showed that 48% and 52% of women had moderate and normal PFM contractions, respectively. Whereas, in posterior area, we observed that moderate and normal contractions represented 24% and 72% respectively. There was statistical concordance in 76% of cases (p < 0.00014) when both positions of PFM evaluation were compared (Table-1). Ho- wever, there was no statistical correlation between orgasm and subjective PFM evaluation neither in anterior nor in posterior areas regarding the vagi- nal introitous. Perineometer evaluation of PFM streng- th was significantly higher in standing position when compared to the others (Table-2). Time of PFM contraction was significantly longer in the standing position (Table-3). There was not statisti- cal difference in the PFM strength, in the different test positions, in women with orgasm compared to those who had not orgasm (Table-3). DISCUSSION Mean age of menarche was 12 years old what is in agreement with literature (17). Some au- thors consider menarcheal age important because Table 1 - Association between the bidigital vaginal palpation in anterior and posterior areas of vaginal introitus according to Amaro’s classification (4). SE posterior SE anterior Grade 2 Grade 3 Total Grade 2 12 (24%)* 0 (0.0 %) 12 (24%) Grade 3 12 (24%) 26 (52%)* 38 (76%) Total 24 (48%) 26(52%) 50 (100%) * Concordance level in moderate grade = 24 % and normal grade = 52%; p < 0.00014 SE = Subjective evaluation Table 2 - Maximum amplitude (cmH2O) (median and range) and time (second) (mean ± sd) of PFM contractions in objective evaluation of PFM strength using perineometer (cmH2O) in different positions. Different lower case letters indicate when groups were significantly different at the same moment. Objective evaluation of PFM Body Position P1 P2 P3 P4 Statistical Analysis Median and range of PFM strength (cmH2O) 16.30a (6.6 - 55.3) 15.60a (7.0 - 59.0) 19.30a (3.6 - 87.3) 28.65b (12.6 - 96.3) p < 0.000 Mean and Standard deviation of PFM contraction time (second) 7.26 ± 1.72a 7.16 ± 1.33a 7.68 ± 1.75a 8,45 ± 2.33b p < 0.000 P1: supine; P2: Bent-Knee lying; P3: Sitting; P4: standing IBJU | pelvic floor Muscle strength and correlation with sexual activity 851 it is influenced by environmental and genetic fac- tors, and also it may be determinant for sexual maturity (17), demonstrating that our population presents these homogenous characteristics. In our population, BMI was considered normal according to WHO, demonstrating that obesity did not influence outcomes. Some authors consider that this fact could worsen SUI or pelvic disorders (18,19). In our study, there was not in- fluence of this parameter in the results. Frawley et al. (13), using different metho- ds for PFM evaluation, observed higher reliabi- lity using manometry in comparison to TDP as- sessment. However, other authors (20) reported a strong correlation between EMG and TDP in continent women without PFM disorders, sho- wing that the best methods of PFM assessment are somehow controversial. In our study, we assessed PFM strength through transvaginal digital palpa- tion in anterior and posterior areas and observed statistical concordance between both methods in 76% of cases, demonstrating that this assessment may be used in any of these positions. At the mo- ment, there is no report regarding this subject in literature. Maximum amplitude and time of PFM con- tractions in objective evaluation of PFM strength using perineometer in standing position were sig- nificantly higher in comparison to the other po- sitions. This fact could be explained because in standing position the pelvic floor muscles suffer of gravity effects and respond with their contrac- tion thereby increasing their strength. Some authors reported the relation betwe- en orgasm and sexual arousal and PFM streng- th (7). Other authors observed that PFM function improvement using perineal exercise postpartum (21) or surgical procedure performed to pelvic flo- or dysfunctions can improve the sexual function (22). In our series, there was no statistical correla- tion between PFM strength and orgasm. The fact that we have not used a more specific and com- plete sexual function questionnaire, which could cause bias, suggests that further research in speci- fic population is necessary. CONCLUSIONS There was statistical concordance in 76% of cases when PFM strength, in anterior and pos- terior areas, was assessed using transvaginal digi- tal palpation. Objective evaluation of PFM streng- th was significantly higher in standing position when compared to the other positions. Orgasm does not seem to be affected by PFM strength. Further studies should be performed in nullipa- rous continent women to elucidate the effects of different test positions and orgasm in the pelvic floor muscle strength. ABBREVIATIONS PFM = pelvic floor muscle) TDP = transvaginal digital palpation WHO = World Health Organization BMI = body mass index Table 3 - Association between Maximum amplitude (cmH2O) (median and range) of PFM contractions in objective evaluation of PFM strength using perineometer in different positions and presence or not of orgasm. PFM Strength in different body positions (cmH2O) Orgasm Absent (9/50 – 18%) Present (41/50- 82%) Statistical Analysis P1 (range) 14.30 (6.60-27.00) 16.60 (6.60-55.30) p = 0.357 P2 (range) 15.30 (8.00-34.30) 15.60 (7.00-59.00) p = 0.919 P3 (range) 15.60 (6.00-36.00) 20.00 (3.60-87.30) p = 0.086 P4 (range) 30.60 (15.60-92.30) 27.30 (2.60-96.00) p = 0.649 P1: supine; P2: Bent-Knee lying; P3: Sitting; P4: standing IBJU | pelvic floor Muscle strength and correlation with sexual activity 852 UI = urinary incontinence EMG = electromyography MRI = resonance imaging SUI = stress urinary incontinence CONFLICT OF INTEREST None declared. REFERENCES 1. Amaro JL, Moreira EC, De Oliveira Orsi Gameiro M, Pa- dovani CR: Pelvic floor muscle evaluation in incontinent patients. Int Urogynecol J Pelvic Floor Dysfunct. 2005; 16: 352-4. 2. Shafik A: The role of the levator ani muscle in evacuation, sexual performance and pelvic floor disorders. Int Urogy- necol J Pelvic Floor Dysfunct. 2000; 11: 361-76. 3. 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Int Urogynecol J Pelvic Floor Dysfunct. 2009; 20(Suppl 1): S45-50. _______________________ Correspondence address: João Luiz Amaro, MD Faculdade de Medicina de Botucatu, Departamento de Urologia Botucatu, São Paulo, 18618-970, Brasil Telephone: + 55 014 3811-6271 E-mail: jamaro@fmb.unesp.br