The functionality of the pelvic floor musculature (PFM) assists in the support of pelvic organs as well as provides urinary, fecal continence and sexual functions within normal limits. For the PFM to be considered functional, it is necessary that strength, resistance, relaxation capacity, superficial sensitivity, tonus, and proprioception are present in a harmonious way. Changes in one or more of these components can trigger, for example, urinary incontinence (UI).

To Identify the sensory and muscle functions of the pelvic floor and UI and their correlations in young nulliparous women.

A descriptive, observational, and cross-sectional study was carried out. The sampling process was of the convenience type, with women aged between 18 and 30 years old, nulliparous, who had never been pregnant and who were not menstruating on the day of the assessment selected. The evaluation was carried out through the application of questionnaires (socio-clinical questionnaire, International Consultation on Incontinence Questionnaire-Short Form) and, later, by physical examination evaluating the superficial sensitivity, the tonus of the perineal body, tonus of the external anal sphincter and strength of MAP through the Perfect scheme. Data were analyzed using the Statistical Program for Social Sciences (version 23) considering a significance level of 5%.

The sample consisted of 45 women with a mean age of 22.18 ± 3.15 years. The prevalence of UI was 31.11%, with the majority referring a feeling of incomplete emptying and 17.77% referring a situation of urinary urgency. The entire sample showed normal sensitivity. Changes in perineal body and external anal sphincter tone were observed in 26.6% and 15.5%, respectively. The group with UI showed more muscle weakness (p=0.04) and less ability to repeat PFM contractions (p=0.02). There was a correlation between PFM functions and the presence of UI in the components of muscle strength (R=-0.78), maintenance of muscle contraction capacity (R=-0.60), repetition potential (R=-0.65) and presence of contraction of the lower abdominal muscles (R=0.55).

UI is directly related to muscle weakness, difficulty maintaining the contraction, lack of ability to repeat PFM contractions and the presence of co-contraction of lower abdominal muscles.

In scientific terms, it was shown that, in terms of MAP, for the development of UI, muscle strength is not a single factor to be considered, considering the importance of other parameters. In clinical terms, this study underscores the importance of considering motor, but also sensory, aspects when evaluating PFM functionality.