Endosonographically diagnosed postpartum anal sphincter defects and the association with pain and dyspareunia.

Huber M1, Larsson C2, Lehmann J3, Strigård K1, Lindam A4, Tunón K1

Research Type

Clinical

Abstract Category

Pregnancy and Pelvic Floor Disorders

Abstract 103
Pelvic Pain and Inflammation
Scientific Podium Short Oral Session 13
Thursday 28th September 2023
09:30 - 09:37
Theatre 102
Pain, Pelvic/Perineal Pelvic Floor Questionnaire Sexual Dysfunction Prospective Study
1. Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, Umeå, Sweden, 2. Department of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden, 3. Department of Surgery, Östersund Hospital, Östersund, Sweden, 4. Department of Public Health and Clinical Medicine, Unit of Research, Education and Development, Östersund Hospital, Umeå University, Umeå, Sweden
Presenter
Links

Abstract

Hypothesis / aims of study
Pelvic floor pain and dyspareunia are both important entities of postpartum pelvic pain, often concomitant and associated with perineal tears during vaginal delivery. However, the association between postpartum endosonographically diagnosed anal sphincter defects, pelvic floor pain, and dyspareunia has not been fully established. The association between sonographic defects and anal incontinence is well known (1), and one study aimed at evaluating parturition mode recommendations following obstetric anal sphincter injuries found that dyspareunia was more common in patients with residual external anal sphincter defects (2). We aimed to determine the prevalence of postpartum anal sphincter defects using three-dimensional endoanal ultrasonography (3D-EAUS). The primary outcome was association of postpartum sonographic sphicter defects with symptoms of pelvic floor pain and dyspareunia. Secondary outcome was risk factors for postpartum sonographic anal sphicter defect.
Study design, materials and methods
This study was part of a large interdisciplinary project involving birth-related perineal injuries, endoanal ultrasonography and postpartum pelvic floor disorders. The present study is a prospective cohort study that followed 239 primiparas from birth to 12 months postdelivery. Anal sphincters were assessed with 3D- EAUS three months postpartum. Volume recording was performed by a trained midwife in a specialized outpatient clinic, using a Flex Focus 500 Ultrasound Machine (BK Medical ApS, Herlev, Denmark) with an 8838 axial endoscopic probe at 12 MHz. Endosonographic datasets were analyzed using proprietary software (BK viewer) on a personal computer by one of the authors who was blinded to all clinical, demographic, and delivery data. A sonographic sphincter defect was defined as a discontinuity in the endosonographic image of the internal anal sphincter (IAS, hypoechoic ring) or external anal sphincter (EAS, mixed echoic ring) and/or characterized by the loss of normal architecture in the appearance of the IAS and/or EAS on ultrasonography. Self-reported pelvic floor function data were obtained using a web-based questionnaire distributed one year after delivery. Adaptive questioning processes were used in cases where supplementary questions addressed further specifications regarding the occurrence of symptoms such as dyspareunia. The scored items of the questionnaire were validated. The survey was conducted voluntarily, and the patient provided consent by logging in with their individual code and submitting the results. Descriptive statistics were compared between the patients with and without sonographic defects, and the association between sonographic sphincter defects and outcomes were analyzed using logistic regression. Analysis of power was performed in the initial study of the project; because the current study is a follow-up study involving the same cohort, power analysis was not applicable. STROBE guidelines were followed. An image of a sonographic anal sphincter defect 3 months postpartum is presented in Figure 1.
Results
At three months postpartum, 48/239 (20%) patients had sonographic anal sphincter defects on 3D-EAUS, of which 43 (18%) were not clinically diagnosed with obstetric anal sphincter injury at the time of delivery. Patients with sonographic defects had higher fetal weight than those without defects, and a perineum <2 cm before the suture was a risk factor for defects (odds ratio [OR], 6.9). One year after delivery, most of the patients were sexually active; however, 30 (13%) had no active sexual relations. Patients with sonographic defects had a higher probability of not having sexual relations (OR, 3.4; 95% CI, 1.4–8.0). Dyspareunia was experienced by 39% of the patients who were sexually active. Additionally, the risk of experiencing dyspareunia was elevated in those with defects (OR, 2.4; 95% CI, 1.4–8.0). The feeling of being too tight (15%) was more common than the feeling of being too wide (9%), with no statistical differences between the groups; however, feeling too tight was reported by 24% in the defect group. 
Perineal pain was experienced by 33 (15%) patients, and 14 reported pain severe enough to prevent most activities in the last three months. Perineal pain was present in both groups, with an elevated risk in the defect group (OR, 2.3; 95% CI, 1.0–5.1). Of those with perineal pain (n=33), 22 were sexually active and nine had no sexual relations. The coexistence of dyspareunia and perineal pain in sexually active women is presented in Figure 2.
Interpretation of results
A sonographic defect on postpartum endoanal ultrasound is a potential prognostic factor for future pelvic floor pain and/or sexual dysfunction, indicating that ultrasonographic imaging may be beneficial during postnatal follow-up. Additionally, a perineal height <2 cm, measured by bidigital palpation immediately postdelivery, was a significant risk factor for sonographic anal sphincter defects. These findings have implications for the clinical setting, including addressing these issues in the early postnatal period to avoid the development of chronic pain, as well as for auditing repair and secondary prevention. Evidence from other studies suggests that sonographic follow-up at 10–12 weeks postpartum in high-risk patients might reduce the morbidity arising from perineal tears (3).
Concluding message
In summary, our findings suggest an association between postpartum sonographic anal sphincter defects, pelvic floor pain, and dyspareunia. Patients at risk of developing pelvic pain and dyspareunia should be identified early in the post-partum period to initiate adequate treatment. A multimodal approach to address all aspects of pain is suggested.
Figure 1 Fig 1. Sonographic anal sphincter defect of both the external (EAS – between angles) and internal (IAS – between arrows) anal sphincter muscles three months postpartum using three-dimensional endoanal ultrasound..
Figure 2 The coexistence of dyspareunia and perineal pain in sexually active women (n=209)
References
  1. Starck M, Bohe M, Valentin L. The extent of endosonographic anal sphincter defects after primary repair of obstetric sphincter tears increases over time and is related to anal incontinence. Ultrasound Obstet Gynecol. 2006;27:188-197.
  2. van der Vlist, M., Oom, D., van Rosmalen, J. et al. Parturition mode recommendation and symptoms of pelvic floor disorders after obstetric anal sphincter injuries. Int Urogynecol J 31, 2353–2359 (2020)
  3. Bellussi F, Dietz HP. Postpartum ultrasound for the diagnosis of obstetrical anal sphincter injury. Am J Obstet Gynecol MFM. 2021;3:100421.
Disclosures
Funding This study was funded by grants from the Unit of Research, Education and Development, Region Jämtland-Härjedalen, and VisareNorr, Northern County Council, Sweden. The funding sources had no impact on the design and execution of the study or on the writing of the manuscript. Clinical Trial Yes Registration Number The trial is registered at ISCRTN: 18006769. RCT No Subjects Human Ethics Committee Regional Ethical Review Board of Umeå Helsinki Yes Informed Consent Yes
Citation

Continence 7S1 (2023) 100821
DOI: 10.1016/j.cont.2023.100821

09/10/2024 11:16:33