Female pelvic floor dysfunctions are common.  Given the differing phenotypic presentations across females with these dysfunctions, effective conservative, pharmacological and surgical care options are all important.  Although individualized and supervised pelvic floor muscle training is currently established as the most effective conservative care strategy (1), adjunctive therapies are often used to further augment outcomes or better align with patient preferences for care.   Electrical muscle stimulation (EMS) represents a long standing established conservative management strategy currently recommended to be used as an adjunctive, rather than stand alone therapy (2).  Advances in technology have changed the landscape of available EMS applications and options. Variations of conventional low frequency intravagnal EMS, are now available through mHealth applications that can be independently used at home.  Novel, surface or extravginal applications of EMS notably, high frequency electromagnetic stimulation, has been proposed as an effective “non-invasive” alternative to intravaginal EMS (3).  The purpose of this study was three fold: 1) To review the current efficacy of EMS for female pelvic floor dysfunction; 2) To describe the efficacy of intravaginal EMS and extravaginal EMS, 3) To describe the efficacy of low frequency EMS and high frequency specifically for female pelvic floor dysfunction.

We conducted a systematic scoping review of the literature searching Medline, Embase, and CINAHL databases. Eligible articles from the last five years included females with pelvic floor muscle dysfunctions of any type and the use of EMS for conservative management.  Following established inclusion/exclusion criteria, two reviewers independently screened, reviewed, and extracted data on study design, study population, type of EMS technology, EMS intervention protocols, and outcomes related to improvement of pelvic floor muscle dysfunction.

The database search yielded 1407 results and a final 38 articles (level of evidence 2-5) were retained for this review. Refer to flow diagram. Studies were categorized according to EMS type being intravaginal (n=13), extravaginal (n=10), and unspecified (n=15).  In addition, they were categorized according to low frequency EMS, less than 50 Hz (n=11), high frequency EMS, equal to or higher than 50Hz (n=14) or unspecified (n=10).  Populations characteristics included urinary incontinence, fecal incontinence, over active bladder, sexual dysfunction and vaginal laxity.  Outcomes measured spanned the domains of impairment (Eg, pelvic floor muscle strength), self-reported functional (Eg, leaking with physical activity) and self-reported participation (Eg. Quality of Life). Both intravaginal and extravaginal EMS were found improve outcomes across all domains.   Both low and high frequency EMS were founded to be effective across domains.  Urinary incontinence specifically, was found to improve more significantly that other population characteristics, with outcomes favouring high frequency EMS.   Generally, EMS was found to be well tolerated with few reports of minor adverse side effects.

We affirm that EMS serves as an effective adjunct conservative care strategy for for pelvic floor dysfunction, particularly for UI.  That is, EMS should not be used as a stand alone conservative care option, given the superiority of individualized pelvic floor muscle training for the populations studied.  Outcomes appeared to favour high frequency EMS.  Given the effectiveness of various forms of EMS, patient preference factors regarding EMS remain an important consideration which was not adequately captured in this review.

A continuum of EMS applications, including novel intravaginal and extravaginal applications, exist for improving female pelvic floor dysfunction.   All appear to carry a beneficial use as an adjunct conservative management option, particularly for UI.

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Stewart F, Berghmans B, Bø K, Glazener CM. Electrical stimulation with non-implanted devices for stress urinary incontinence in women. Cochrane Database Syst Rev. 2017 Dec 22;12(12):CD012390. doi: 10.1002/14651858.CD012390.pub2.
Silantyeva E, Zarkovic D, Astafeva E, Soldatskaia R, Orazov M, Belkovskaya M, Kurtser M; Academician of the Russian Academy of Sciences. A Comparative Study on the Effects of High-Intensity Focused Electromagnetic Technology and Electrostimulation for the Treatment of Pelvic Floor Muscles and Urinary Incontinence in Parous Women: Analysis of Posttreatment Data. Female Pelvic Med Reconstr Surg. 2021 Apr 1;27(4):269-273. doi: 10.1097/SPV.0000000000000807.