Obstetric Pelvic Floor & Anal Sphincter Injuries

SIG Leadership

Chair: Abdul Sultan (UK)


Perineal and vaginal injuries are common during childbirth, and up to 80% of primiparous women need suturing after a vaginal delivery. First and second degree perineal injuries rarely cause long-term health problems, but third and fourth degree injuries, which include anal sphincter muscle trauma, are associated with increased risk for anal incontinence (AI), pain, discomfort and sexual dysfunction. Reported incidence of obstetric anal sphincter injury (OASI) varies from 1 to 6% in different delivery units and countries. Main risk factors for OASI are large infant birth weight and instrumental delivery, but OASI occurs even in otherwise uncomplicated deliveries.

Injuries in deep muscles such as levator ani are also common during vaginal delivery with reported incidences from 13 to 30% among primiparous women. Risk factors for levator ani muscle trauma are similar to OASI risk factors – large fetal head circumference and instrumental delivery, especially forceps. OASI is associated with levator ani muscle avulsion, also indicating uniform risk profile for these complications. Levator ani muscle injury is associated with pelvic organ prolapse, commonly needing surgical repair later in life. Similarly, risk for urinary incontinence increases with delivery of a large infant and with increasing parity. Non-obstetrical factors such as aging, menopause, and being overweight are also associated with the mentioned pelvic floor disorders, but previous injuries during childbirth may increase the risk of complaints following aging.

Existing studies indicate that pelvic floor injuries and also complaints and complications associated with these injuries can be reduced. Choosing clinical routines that reduce pelvic floor trauma (manual perineal protection, correct use of episiotomy, avoiding forceps delivery, optimal birth positions) will reduce the OASI risk during childbirth. Optimal management of the perineum immediately after delivery (diagnostics and repair) reduce the occurrence of anal and urinary incontinence. Pelvic floor muscle training before and after childbirth may also reduce the risk of incontinence later in life. There is still much to do to improve women’s health during and after vaginal delivery, and this Special Interest Group aims at adding knowledge and education for birth attendants around the world.

Aims and Objectives

The main aim for this Special Interest Group is to study clinical routines optimal for reducing pelvic floor trauma during delivery and focusing mainly on obstetric anal sphincter trauma. Additionally, we aim to:

  • Add knowledge on managing pelvic floor trauma to reduce complications and complaints for the woman.
  • Add knowledge on health effects of obstetric pelvic floor trauma.
  • Develop educational tools for easy and economical knowledge transfer for prevention of pelvic floor trauma.
  • Promote safe vaginal birth globally to reduce the need for unnecessary caesarean deliveries.

Existing Knowledge and Knowledge Gaps

Maternal, fetal and obstetrical risk factors for OASI have been widely studied with focus on non-modifiable patient related factors such as maternal age, ethnicity, fetal weight and head size, but many women suffering from OASI have no risk factors, as most OASI occur during spontaneous delivery with a normal size infant. Therefore, attempts to create risk-scoring systems to predict OASI on individual level have not been successful. OASI is an infrequent event and often occurs without predicting factors, when a normal childbirth is expected.

Many pelvic floor disorders are associated with vaginal delivery, especially “difficult delivery” with a large infant and/or instrumental delivery. Risk factors unrelated to the delivering woman or the infant size, such as the accoucheurs’ management of the second stage of delivery, have been less investigated. Some of the complications might be avoided or at least the risk for the complication might be reduced with choices made during the delivery. Observational studies reveal that clinical routines and choices during delivery may decrease the risk of OASI:

  • Routine use of manual perineal protection
  • Correct use of episiotomy when clinically indicated
  • Correct cutting of episiotomy with a 60° angle at crowning
  • Avoiding median/midline episiotomy
  • Choosing vacuum extraction instead of forceps
  • Birth position
  • Pushing technique

Levator Ani Muscle
Risk factors with OASI are coinciding, but whether the mentioned procedures protect women from levator ani muscle injuries has not been studied. Slower expulsion of fetal head may reduce the risk of levator ani injuries also.

Quality of Life
Methods to assess quality of life among women in fertile age are scarce. Conclusions in previous studies on pelvic floor disorders and quality of life are conflicting. Women with anal incontinence may not score reduced QoL. Whether the measuring tools are not suitable for women in fertile age or these women adapt to a life with anal incontinence is unknown.

Pelvic Floor Muscle Training
The conclusions of existing research of the role of pelvic floor muscle training for treatment and prevention of pelvic floor dysfunction are conflicting, and more research is needed. Training during pregnancy and after delivery needs to be explored.

Group Research

  • There is still need for more research on OASIS, anal incontinence, pelvic organ prolapse, urinary incontinence and quality of life.
  • The combination of obstetrical and non-obstetrical risk factors for pelvic floor injuries need to be assessed.
  • Pelvic floor injuries, delivery and protective clinical routines in different countries and delivery units:
    • Quality of episiotomy with correct angle
    • Frequency of episiotomy use
    • Use of manual perineal protection
    • Postpartum follow-up
    • Patient information/support

Quality of Life Measurement Tool

  • To assess associations between pelvic floor dysfunction and quality of life (QoL) among women in fertile age. The existing questionnaires for QoL may fail to identify effect on QoL among women in fertile age.

Networking and Collaboration

  • Collaboration (interdisciplinary and multi-professional); health care providers
  • Collaboration with midwifery and obstetric colleges and researchers.
  • Health care authorities and policy makers globally

Education and Training

  • Diagnostics and repair
  • Prevention of delivery/pelvic floor injuries
  • Management of incontinence, including all healthcare professionals
  • Education should also be offered in developing countries, where problems with incontinence are notable.
  • Development and implementation of training programs to reduce pelvic floor injuries during vaginal delivery

Patient Information

  • How to seek help in health care
  • How to cope with living with incontinence and pelvic floor dysfunction
  • How to give birth in next pregnancy after pelvic floor injury
  • Pelvic floor muscle training


  • Publications in scientific journals
  • Popularized communication such as social media
  • Patient organizations


The group aims to meet during annual IUGA meetings with additional contact via Skype-meetings and email communication.

The group is multi-professional and international, giving us an opportunity to conduct multi-center clinical studies with large numbers of patients, working alongside IUGA’s Research & Development Committee). We can communicate with clinicians directly ensuring close cooperation with practicing obstetricians, midwives, and urogynaecologists. Knowledge achieved from research may easily and rapidly be implemented without delay through agreed training programs, e.g. Care Bundle in the UK and the national interventional program for reducing the risk of OASIS in Norwegian delivery units. Feedback from clinicians from different cultures can be used to develop studies and education.

Follow the Obstetric Pelvic floor & Anal Sphincter Injuries SIG on the IUGA E- Discussion Forum. Click here or sign up through your IUGA Member Page by clicking the Special Interest Groups box.