Reflex contraction of the levator ani in women symptomatic for pelvic floor disorders.

Abstract

Stress urinary incontinence (SUI) is a common health problem in women. Reflex activation of muscular pelvic floor structures may play a role in preserving continence. In this study we aimed to analyze reflex pelvic floor activity on coughing in women seen for urodynamic testing. In a retrospective cohort study we analyzed the data sets of 191 women who attended a tertiary referral service for multichannel urodynamic testing and four-dimensional pelvic floor ultrasound scan between May 2009 and February 2010. Coughs were registered on volume ultrasound at a minimum of 16 Hz and analyzed by postprocessing at a later date, the operator being blinded against all clinical data. Of 175 analyzable cough volume datasets, a levator reflex was seen in 138 (79%), and clitoral reflex movement in 160 (91%). On multivariable analysis there was a significant relationship between urodynamic stress incontinence (USI) and the absence of a levator reflex (P = 0.045), and a negative relationship with the magnitude of such a reflex (P = 0.046). Reflex timing was not associated with SUI or USI. Reflex contraction of the levator ani can be observed on translabial ultrasound during sudden increases in intra-abdominal pressure. These reflex contractions are common, even in women with symptoms and signs of pelvic floor dysfunction. The observation of a levator reflex on coughing, and its magnitude, show a weak inverse association with the presence of USI.