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Anal sphincter injury

Pelvic Floor Center ® and Colon & Rectal Surgery. Anal Sphincter Injury. (2016)

This article introduces to the general knowledge about Anal Sphincter Injury. The article answers general questions such as: What is a sphincter injury? What causes a sphincter injury? How is a sphincter injury diagnosed? How is a sphincter injury treated? The topic is addressed to patients for an introduction to the problem.


The Management of Postpartum Anal Sphincter Injury

Nihan Gençdal, Emre Ekmekci, Servet Gençdal, Emre Destegül, International Journal of Midwifery Nursing. Vol, 1 Issue 1. IJ MN 13-19 JournalsPub, 2018

Injury to the anal sphincter is recognized as the most common cause of anal incontinence (AI) and anorectal symptoms in otherwise healthy women. The true prevalence of AI related to anal sphincter injury (ASI) may be underestimated. The reported rates of AI following the primary repair of ASI range between 15% and 61%, with a mean of 39%. This high prevalence highlights the need to ensure our surgical techniques and postoperative management is optimal. Building a right diagnosis at time of damage will help acceptable repair and may avoid future indulgence. This review drafts the elements, diagnosis, and administration of obstetric anal sphincter damage.


A surgeon in the delivery room.

Małgorzata Kołodziejczak, Przemysław Ciesielski, Fabian Kamiński, Borgis-Nowa Medycyna 4/2017, s. 164-170, DOI: 10.25121/NM.2017.24.4.164, 2017

Most of perineal tears are managed by gynaecologists, who rarely consult with surgeons. Consultation most often takes place in the case of extensive damage to the anal sphincters and rectal wall, i.e. fourth-degree perineal tears. This situation is particularly likely in multispeciality hospitals featuring both gynaecological/obstetric and surgical departments. The paper discusses the guidelines for urgent management of perineal sphincter tears based on the current guidelines developed by the Royal College Obstetricians and Gynaecologists as well as recent literature. We also wish to share our practical observations from reconstructive surgeries after obstetric anal sphincter injuries. In most cases, a correctly performed anal sphincter repair causes no permanent dysfunctions, whereas inappropriately managed third- or fourth-degree perineal tears may lead to complications, such as poor gas and faecal continence, anovaginal or rectovaginal fistula, haematoma, wound infection, abscess and, in extreme cases, severe septic complications.


Obstetrical Anal Sphincter Injuries and the Need for Adequate Care

Elliot V, Yaskina M, Schulz J, Female Pelvic Med Reconstr Surg. 109-112, 2019.

Background: An estimated 4% to 6.6% of women delivering vaginally sustain obstetrical anal sphincter injuries (OASI). Despite this, a gap exists in the provision of postpartum care to women globally. Given the negative impact of OASI, action is needed, and multidisciplinary perineal clinics can help. Consequently, such a clinic was established in 2011 at the Royal Alexandra Hospital (RAH), a tertiary care center in Edmonton, Alberta. Objective: This study assesses the state of perineal clinics specializing in OASI internationally and locally by investigating the literature for descriptions of specialized perineal clinics for women with OASI, describing the RAH perineal clinic, and assessing the prevalence of OASI at the RAH in the context of the clinic. Methods: A search of peer-reviewed literature was conducted on Medline and observations and interviews of RAH perineal clinic staff were conducted, as was a medical chart review. Results: Articles describing only 10 perineal clinics specializing in OASI were found, with varying structures. The multidisciplinary RAH clinic, like one other clinic, has a strong physiotherapy focus, with education and Pilates classes and one-on-one appointments offered by pelvic floor physiotherapists. In 2016, of the 326 (6.9%) vaginal deliveries that resulted in OASI at the RAH, only 66.0% (215) were referred to the clinic. Conclusions: Multidisciplinary perineal clinics are needed globally. Despite the creation of the perineal clinic at the RAH, women continue to lack specialized care after OASI. It is crucial that healthcare professionals specializing in OASI share their experiences to establish best practices and create new, and improve existing, perineal clinics.


Obstetric anal sphincter injuries: Incidence, risk factors, consequences and prevention (PhD thesis)

Katariina Laine, Series of dissertations submitted to the Faculty of Medicine, University of Oslo No. 1635 ISBN 978-82-8264-751-9, 2013

The aim of this study was to assess the prevalence and risk factors of anal incontinence in an unselected pregnant population at second trimester. A survey of pregnant women attending a routine ultrasound examination was conducted in a university hospital in Oslo, Norway. A questionnaire consisting of 105 items concerning anal incontinence (including St.Mark’s score), urinary incontinence, medication use and co-morbidity was posted to women when invited to the ultrasound examination. Results: Prevalence of self-reported anal incontinence (St. Mark’s score ≤ 3) was lowest in the group of women with a previous cesarean section only (6.4%) and highest among women with a previous delivery complicated by obstetric anal sphincter injury (24.4%). Among nulliparous women the prevalence of anal incontinence was 7.7%, and was associated to low educational level and co-morbidity. Prevalence of anal incontinence increased with increasing parity. Urinary incontinence was associated to anal incontinence in all parity groups. Conclusions: Anal incontinence was most frequent among women with a history of obstetric anal sphincter injury. Other obstetrical events had a minor effect on prevalence of anal incontinence among parous women. Prevention of obstetrical sphincter injury is likely the most important factor for reducing bothersome anal incontinence among fertile women. Introduction: Anal incontinence is a bothersome ailment associated with many health complaints and discomfort in daily life; hygienic problems, limitations in occupational and social life, sexual dysfunction, reduced quality of life and altered self-esteem. Anal incontinence (AI) is defined as involuntary loss of flatus or feces. Prevalence and severity of anal incontinence is measured by patient self-reporting, no objective assessment methods exist. Obstetric anal sphincter injury (OASIS) is one of the main causes for female AI reported in non-pregnant women. Additionally, multiple vaginal deliveries can increase the risk of AI regardless of anal sphincter injury . Age, obesity and medical conditions such as diabetic neuropathy and gastrointestinal disorders also increase the risk of anal incontinence. Prevalence of anal incontinence among women differs largely (2-28%) in previous studies, and differs between different study populations . Postpartum studies show a high prevalence of AI in women having suffered OASIS, 38-59% . Women attending gynecological out patient clinics have higher prevalence of AI (16-28%) compared with the general female population (4.4%). Women with pelvic floor disorders have higher prevalence of AI than women without pelvic floor disorders. Community based studies show differences in prevalence of AI between age groups, with increasing prevalence by increasing age. Most frequent AI is found among nursing home residents (50-60%), among the oldest women with frequent additional complaints and co-morbidity. Few previous studies have assessed the prevalence of anal incontinence among pregnant women and few studies have included nulliparous women. The aim of this study was to assess the prevalence and risk factors for anal incontinence in an unselected female population across parity groups in second trimester of pregnancy.


Non-invasive obstetric anal sphincter injury diagnostics using impedance spectroscopy.

Borycka-Kiciak, K., Młyńczak, M., Kiciak, A., Pietrzak, P., & Dziki, A., Scientific reports, 9(1), 7097, 2019

Obstetric anal sphincter injuries are the most common cause of fecal incontinence in women yet remain under-diagnosed. The aim of this study was to assess the suitability of impedance spectroscopy for diagnosing sphincter injuries arising during delivery. This was a prospective single-center study. 22 female patients were included: 10 with symptoms of sphincter dysfunction, in the early postpartum period, and 12 unaffected, in the distant period of more than 2 years after natural delivery. The presence, extent and severity of anal sphincters injury was assessed by measuring the sphincter parameters in physical examination, the degree of sphincter damage in endoanal ultrasound imaging and the sphincters function parameters in anorectal manometry. All measurements were used as references and compared with the outcomes from the impedance spectroscopy models. Impedance spectroscopy showed the highest precision (with mean accuracy of 83.9%) in relation to transanal ultrasonography. 74.1% of its results corresponded to the results of rectal physical examination and 76.7% - to those of anorectal manometry. The method showed the highest accuracy in the assessment of the sphincter’s parameters, both anatomically and functionally. New impedance spectroscopy techniques hold promise for detecting obstetric anal sphincter injuries.


Anal sphincter defects and fecal incontinence 15-24 years after first delivery: a cross-sectional study.

Rodrigo A Guzmán Rojas, Kjell Å Salvesen, Ingrid Volløyhaug, Ultrasound Obstet Gynecol, 51(5), DOI: 10.1002/uog.18827, 2018

Objectives: To establish the prevalence of external (EAS) and internal (IAS) anal sphincter defects present 15-24 years after childbirth according to mode of delivery, and their association with development of fecal incontinence (FI). The study additionally aimed to compare the proportion of women with obstetric anal sphincter injuries (OASIS) reported at delivery with the proportion of women with sphincter defect detected on ultrasound 15-24 years later. Methods: This was a cross-sectional study including 563 women who delivered their first child between 1990 and 1997. Women responded to a validated questionnaire (Pelvic Floor Distress Inventory) in 2013-2014, from which the proportion of women with FI was recorded. Information about OASIS was obtained from the National Birth Registry. Study participants underwent four-dimensional transperineal ultrasound examination. Defect of EAS or IAS of ≥ 30° in at least four of six slices on tomographic ultrasound was considered a significant defect and was recorded. Four study groups were defined based on mode of delivery of the first child. Women who had delivered only by Cesarean section (CS) constituted the CS group. Women in the normal vaginal delivery (NVD) group had NVD of their first child and subsequent deliveries could be NVD or CS. The forceps delivery (FD) group included women who had FD, NVD or CS after FD of their first born. The vacuum delivery (VD) group included women who had VD, NVD or CS after VD of their first born. Multiple logistic regression was used to calculate adjusted odds ratios (aORs) for comparison of prevalence of an EAS defect following different modes of delivery and to test its association with FI. Fisher's exact test was used to calculate crude odds ratios (ORs) for IAS defects. Results: Defects of EAS and IAS were found after NVD (n = 201) in 10% and 1% of cases, respectively, after FD (n = 144) in 32% and 7% of cases and after VD (n = 120) in 15% and 4% of cases. No defects were found after CS (n = 98). FD was associated with increased risk of EAS defect compared with NVD (aOR = 3.6; 95% CI, 2.0-6.6) and VD (aOR = 3.0; 95% CI, 1.6-5.6) and with increased risk of IAS defect compared with NVD (OR = 7.4; 95% CI, 1.5-70.5). The difference between VD and NVD was not significant for EAS or IAS. FI was reported in 18% of women with an EAS defect, in 29% with an IAS defect and in 8% without a sphincter defect. EAS and IAS defects were associated with increased risk of FI (aOR = 2.5 (95% CI, 1.3-4.9) and OR = 4.2 (95% CI, 1.1-13.5), respectively). Of the ultrasonographic sphincter defects, 80% were not reported as OASIS at first or subsequent deliveries. Conclusions: Anal sphincter defects visualized on transperineal ultrasound 15-24 years after first delivery were associated with FD and development of FI. Ultrasound revealed a high proportion of sphincter defects that were not recorded as OASIS at delivery.