Obstetric levator ani muscle injuries: current status

Ultrasound Obstet Gynecol. 2012 Apr;39(4):372-83. doi: 10.1002/uog.11080.


Levator ani muscle (LAM) injuries occur in 13-36% of women who have a vaginal delivery. Although these injuries were first described using magnetic resonance imaging, three-dimensional transperineal and endovaginal ultrasound has emerged as a more readily available and economic alternative to identify LAM morphology. Injury to the LAM is attributed to vaginal delivery resulting in reduced pelvic floor muscle strength, enlargement of the vaginal hiatus and pelvic organ prolapse. There is inconclusive evidence to support an association between LAM injuries and stress urinary incontinence and there seems to be a trend towards the development of fecal incontinence. Longitudinal studies with long-term follow-up assessing the LAM before and after childbirth are lacking. Furthermore, the consequence of LAM injuries on quality of life due to prolapse and/or urinary and fecal incontinence have not been evaluated using validated questionnaires. Direct comparative studies using the above-mentioned imaging modalities are needed to determine the true gold standard for the diagnosis of LAM injuries. This would enable consistency in definition and classification of LAM injuries. Only then could high-risk groups be identified and preventive strategies implemented in obstetric practice.

Publication types

  • Review

MeSH terms

  • Adult
  • Delivery, Obstetric / adverse effects*
  • Fecal Incontinence / diagnostic imaging*
  • Fecal Incontinence / etiology
  • Fecal Incontinence / physiopathology
  • Female
  • Humans
  • Imaging, Three-Dimensional / trends
  • Maternal Age
  • Middle Aged
  • Pelvic Floor / diagnostic imaging*
  • Pelvic Floor / injuries*
  • Pelvic Floor / physiopathology
  • Pelvic Organ Prolapse / diagnostic imaging*
  • Pelvic Organ Prolapse / etiology
  • Pelvic Organ Prolapse / physiopathology
  • Pregnancy
  • Risk Factors
  • Ultrasonography
  • Urinary Incontinence, Stress / diagnostic imaging*
  • Urinary Incontinence, Stress / etiology
  • Urinary Incontinence, Stress / physiopathology
  • Uterine Prolapse / diagnostic imaging*
  • Uterine Prolapse / etiology
  • Uterine Prolapse / physiopathology