Biofeedback and the electromyographic activity of pelvic floor muscles in pregnant women

Background: Maintaining continence is among the functions of the pelvic floor muscles (PFM) and their dysfunction can cause urinary incontinence (UI), which is a common occurrence during pregnancy and the puerperal period. Pelvic floor muscle training (PFMT), therefore, is important during pregnancy, although most women perform the muscle contractions unsatisfactorily. Objectives: This study is an exploratory analysis of the results of three electromyographic (EMG) activity biofeedback sessions in pregnant women. Methods: The study sample included 19 nulliparous women with low risk pregnancies. The participants performed three sessions of EMG biofeedback consisting of slow and fast contractions. The average value of the normalized amplitudes of surface electromyography was used to evaluate the results. The linear regression model with mixed effects was used for statistical analysis, with the EMG data normalized by maximum voluntary contraction (MVC). Results: A steady increase in EMG amplitude was observed during each contraction and by the end of the biofeedback sessions, although this difference was only significant when comparing the first tonic contraction of each session (p= 0.03). Conclusions: The results indicate that three sessions of training with biofeedback improved PFM EMG activity during the second trimester in women with low-risk pregnancies. The effectiveness of this protocol should be further investigated in randomized controlled trials.