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

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. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Anal sphincter trauma and anal incontinence in urogynecological patients.

OBJECTIVES: To determine the prevalence of evidence of residual obstetric anal sphincter injury, to evaluate its association with anal incontinence (AI) and to establish minimal diagnostic criteria for significant (residual) external anal sphincter (EAS) trauma. METHODS: This was a retrospective analysis of ultrasound volume datasets of 501 patients attending a tertiary urogynecological unit. All patients underwent a standardized interview including determination of St Mark's score for those presenting with AI. Tomographic ultrasound imaging (TUI) was used to evaluate the EAS and the internal anal sphincter (IAS). RESULTS: Among a total of 501 women, significant EAS and IAS defects were found in 88 and 59, respectively, and AI was reported by 69 (14%). Optimal prediction of AI was achieved using a model that included four abnormal slices of the EAS on TUI. IAS defects were found to be less likely to be associated with AI. In a multivariable model controlling for age and IAS trauma, the presence of at least four abnormal slices gave an 18-fold (95% CI, 9-36; P < 0.0001) increase in the likelihood of AI, compared with those with fewer than four abnormal slices. Using receiver-operating characteristics curve statistics, this model yielded an area under the curve of 0.86 (95% CI, 0.80-0.92). CONCLUSIONS: Both AI and significant EAS trauma are common in patients attending urogynecological units, and are strongly associated with each other. Abnormalities of the IAS seem to be less important in predicting AI. Our data support the practice of using, as a minimal criterion, defects present in four of the six slices on TUI for the diagnosis of significant EAS trauma.

Pelvic floor trauma: does the second baby matter?

OBJECTIVE: To ascertain the effect of a second delivery on pelvic floor anatomy. METHODS: This was a retrospective analysis of data obtained in two perinatal imaging studies. Women were invited for antenatal and two postnatal appointments. All had answered a standardized questionnaire and undergone a clinical examination and translabial four-dimensional ultrasound. Ultrasound volumes were acquired at rest, on Valsalva maneuver and on pelvic floor muscle contraction, and analyzed by postprocessing on a PC. Avulsion was diagnosed on tomographic ultrasound imaging. This study reports data obtained in those women who delivered a second child between the first and second postnatal assessments. RESULTS: Of 715 participants, 94 reported a second birth at their second postnatal appointment on average 2.7 years after their first birth; 65 had a vaginal delivery and 29 a Cesarean section. There were nine attempts at vaginal birth after Cesarean section (VBAC), of which six were successful. When we analyzed the ultrasound findings before and after a second delivery, there was no significant change observed in bladder-neck descent, cystocele descent and hiatal area on Valsalva. Delivery mode of the second birth seemed to have little effect on changes observed between follow-ups, although there was a trend towards increased bladder-neck descent in women after vaginal delivery. On reviewing patients diagnosed with avulsion at their 2-3-year visit and comparing them with findings at the first follow-up visit, we found identical (normal) findings in 87 cases. In five there was an unchanged avulsion. In one case, findings had improved from complete to partial avulsion. There was one new avulsion, in a patient who had delivered her first baby by emergency Cesarean section and her second by vacuum delivery. CONCLUSIONS: A second pregnancy and delivery do not seem to have a major effect on bladder support and/or levator function. However, we documented a case of major levator trauma after VBAC. The issue of pelvic floor trauma after VBAC may have to be investigated further.

Prevalence of anal sphincter injury in primiparous women.

OBJECTIVE: To determine the prevalence of obstetric anal sphincter injuries (OASIS) in a cohort of primiparous women and to evaluate their association with demographic, obstetric and ultrasound parameters. METHODS: This was a retrospective analysis of the ultrasound volume datasets of 320 primiparous women, acquired at 5 months postpartum. Tomographic ultrasound imaging (TUI) was used to evaluate the external anal sphincter (EAS). A significant EAS defect was diagnosed if a defect of > 30° was seen in four or more of six TUI slices bracketing the EAS. RESULTS: Significant EAS defects were found in 69 women (27.9% of those delivered vaginally). In nine of those a third-degree tear was diagnosed intrapartum and was sutured. In 60 women with significant defects there was no documentation of sphincter damage at birth, implying unidentified or occult defects (60/69, 87.0%). Among them, 29 had had a second-degree tear, two a first-degree tear and three an intact perineum. In 31 cases an episiotomy had been performed, with five extensions to a third-degree tear. On multivariate analysis only forceps delivery was significantly associated with OASIS. CONCLUSIONS: In this cohort of primiparous women we found OASIS in 27.9% of vaginally parous women, most of which had not been diagnosed in the delivery suite. There seems to be a need for better education of labor-ward staff in the recognition of OASIS. On the other hand, it is conceivable that some defects may be masked by intact tissue. The significance of such defects remains doubtful. Forceps delivery was the only identifiable risk factor.