Obstetric anal sphincter injuries in spontaneous vaginal births in nulliparous pregnant individuals: a 21-year cohort study based on real-world data (Reply to Letter-to-the-Editor).

Obstetric anal sphincter injuries in spontaneous vaginal births in nulliparous pregnant individuals: a 21-year cohort study based on real-world data.

Information about the long-term severity and subjective impact of anal incontinence in women after 1 or 2 consecutive obstetrical anal sphincter injuries is still scarce and contradictory. This study aimed to describe the severity and impact of anal incontinence among women with 2 previous deliveries 2 decades after birth and to analyze the relative effect of 1 vs 2 obstetrical anal sphincter injuries in comparison with no obstetrical anal sphincter injuries and the possible influence of obstetrical anal sphincter injury on other pelvic floor disorders. We linked prospectively registered data in the Swedish Medical Birth Register with information from a postal and web-based questionnaire in 2015. Statistics Sweden identified women with 2 vaginal births from 1992 to 1998, and a simple random sample of 11,000 women was drawn from a source cohort of 64,687 women. To achieve equal-sized groups of women with 1 or 2 obstetrical anal sphincter injuries, the latter group was oversampled from 1987 to 2000. The final study cohorts consisted of 6760 women with no obstetrical anal sphincter injury, 357 women with 1 injury, and 324 women with 2 obstetrical anal sphincter injuries. Third- and fourth-degree perineal tears were grouped together for analysis. Anal incontinence was defined as either fecal or isolated gas incontinence, and fecal incontinence was defined as involuntary leakage of solid or liquid stool with or without concomitant gas. Frequencies of leakage of stool and gas were dichotomized into low frequency (less than once a month) and high frequency (several times a month or more often). Pairwise comparisons were analyzed using Fisher exact tests, Mantel-Haenszel statistics, and the Mann-Whitney U test. Trends were analyzed using Mantel-Haenszel statistics and the Spearman rank correlation test. Logistic regression models were used to obtain the age- and body-mass-index -adjusted odds ratios for outcomes. Statistical significance was set at P<.05. The response rate was 65.5% in the randomly selected cohort and 70.1% among women with 2 obstetrical anal sphincter injuries. Bothersome fecal incontinence occurred in 3.3% (212/6458) of women without obstetrical anal sphincter injury, in 10.4% (36/345) (adjusted odds ratio, 3.25; 95% confidence interval, 2.23-4.73) of those with 1 injury, and in 16.5% (52/315) (adjusted odds ratio, 5.16; 95% confidence interval, 3.69-7.22) of those with 2 obstetrical anal sphincter injuries (trend P<.0001). Fecal incontinence was perceived as bothersome in 28.2% (212/753) of women without an obstetrical anal sphincter injury compared with in 43.9% (36/82) and 46.0% (52/113) of those with 1 or 2 obstetrical anal sphincter injuries (trend P<.0001). Leakage of liquid stool occurred in 10.8% (724/6717) of those without injury, in 21.7% (77/355) of women with 1 injury, and 34.9% (113/324) of women with 2 obstetrical anal sphincter injuries (trend P<.0001). Incontinence affecting daily life was reported by 8.6% (577/6672) of women without injury and by 19.7% (69/351) and 29.6% (96/324) of women with 1 and 2 sphincter injuries, respectively (trend P<.0001). The mean Jorge-Wexner score was 2.44, 3.26, and 3.88 for women with no, 1, or 2 sphincter injuries (trend P<.0001). Among women with a Jorge-Wexner score of 6, >50% had bothersome anal incontinence. The adjusted odds ratio for the overall effect of 1 vs 2 obstetrical anal sphincter injuries on measures of anal incontinence was 2.19 (95% confidence interval, 1.68-2.85) and 3.91 (95% confidence interval, 3.06-5.00), respectively, when compared with no obstetrical anal sphincter injury (both P<.0001). Having 1 or 2 obstetrical anal sphincter injuries had no significant effect on other pelvic floor disorders or on lower urinary tract symptoms (P=.73 and P=.69). A consistent additive effect of 1 or 2 sphincter injuries on the severity and impact of anal incontinence was observed in women 2 decades after 2 vaginal births. This information is important for healthcare economics, clinical practice, and policy.

The prevention of perineal trauma during vaginal birth

Internal anal sphincter injury in the immediate postpartum period; Prevalence, risk factors and diagnostic methods in the Swedish perineal laceration registry

Operative vaginal delivery (OVD) has experienced a decline, primarily driven by decreasing rates of forceps-assisted vaginal delivery (FAVD). FAVD rates have been suspected to be declining to a point where recovery of this skill may be improbable. While there are numerous reasons for this decline ranging from lack of training to patient preferences, the same period has been suspected to have worsening morbidity with FAVD. Concerns have been raised with respect to obstetric anal sphincter injuries (OASIS). To characterize national trends in OVD and risk factors for associated OASIS between 2016 and 2023, assessing changes in OVD utilization and the associated risk of OASIS. This is a cross-sectional study using National Vital Statistics System birth certificate data between 2016 to 2023 to identify temporal trends in OVD and OASIS rates. Liveborn deliveries undergoing trial of labor from 34 weeks and 0 days to 42 weeks and 6 days to patients aged 16-50 years of age were included. Pregnancies with multifetal gestations, fetal anomalies, non-vertex presentations, and unknown mode of delivery were excluded. Temporal trends in OVD and OASIS were assessed using Joinpoint regression. Multivariable logistic regression models were fit to assess the association between OASIS and OVD, adjusting for maternal demographics and comorbidities. Of the 21,191,398 liveborn deliveries identified, 18,054,141 (85.2%) were spontaneous vaginal births, 2,303,168 (10.9%) were cesarean after trial of labor, 136,927 (0.6%) were forceps-assisted vaginal deliveries (FAVD), and 697,162 (3.3%) were vacuum-assisted vaginal deliveries (VAVD) with a OVD composite of 3.9%. OVD rates decreased significantly from 4.6% to 4.1% (annual average percent change (AAPC): -1.6%, 95% CI: -1.9% to -1.4%). Specifically, FAVD rates declined from 0.8% to 0.6% (AAPC: -3.1%, 95% CI: -3.7% to -2.6%) and VAVD rates declined from 3.8% to 3.4% (AAPC -1.4%, 95%CI: -1.7% to 1.1%). OASIS rates in the overall group did not significantly change (AAPC 1.4%, 95%CI: -2.1% to 4.4%), although among FAVD, there was a significant increase in rates of OASIS from 9.3% in 2016 to 14.0% in 2023 (AAPC 4.8%, 95%CI: 2.3% to 7.0%). Adjusted multivariable logistic regression noted higher likelihood of OASIS in FAVD (aOR 9.50, 95%CI: 9.33 to 9.66), and VAVD (aOR 3.90, 95%CI: 3.85 to 3.94) when compared to spontaneous vaginal birth, adjusting for maternal age, maternal BMI, and maternal comorbidities including diabetes and hypertensive disorders. The primary finding in this study was a national decline in OVD with significantly greater declines in FAVD and an increasing rate of OASIS among FAVD. Whether targeted interventions to enhance training in safe FAVD may increase proficiency in this technique remains to be seen.

BackgroundIn view of the reported increase in obstetric anal sphincter injuries, the objective of this study was to evaluate the incidence of such injuries over time and the associated risk and protective factors.MethodsThis was a retrospective cohort study from a national database of 168 137 primiparous women with term, singleton, cephalic, vaginal delivery between 2008 and 2014. The main outcome measure was obstetric anal sphincter injury. A multivariate regression model was used to identify risk and protective factors.ResultsAge >19 years, birthweight >4000 g, and operative vaginal delivery were independent risk factors for obstetric anal sphincter injuries. Mediolateral episiotomy increased the risk for obstetric anal sphincter injuries in spontaneous vaginal birth (number needed to harm 333), whereas it was protective in vacuum delivery (number needed to treat 50). From 2008 to 2014, there was an increase in the rate of obstetric anal sphincter injuries (2.1% vs 3.1%, P < .01), vacuum deliveries (12.1% vs 12.8%, P < .01), and cesarean delivery after labor (17.1% vs 19.4%, P < .01), while forceps deliveries (0.4% vs 0.1%, P < .01) and episiotomy rate decreased (35.9% vs 26.4%, P < .01).ConclusionsEpisiotomy may be a risk or protective factor depending on the type of episiotomy and the clinical setting in which it is used. Our study supports a restrictive use of mediolateral episiotomy in spontaneous vaginal deliveries. In vacuum deliveries mediolateral episiotomy may help prevent obstetric anal sphincter injuries.

High-Temperature Gas-Cooled Reactors (HTRs) permit nuclear energy to be applied to a number of fossil-fuel conversion processes. In general, these processes require application of a steam-methane reformer; for such applications, an HTR with an outlet coolant temperature in the range of 850 to 950/sup 0/C is required. Such systems are applicable to chemicals production, a number of fossil conversion processes, as well as to chemical heat pipes. A relatively early application of reformer HTRs might be the steam reforming of methane to produce synthesis gas for chemicals production. At the same time, one of the coal conversion processes examined has energy requirements such that a steam-cycle HTR having an outlet coolant temperature of 750/sup 0/C will provide about 90% of the total primary energy requirements. In general, screening studies of coal and oil shale conversion processes indicate that coupling HTR technology with fossil conversion technologies can lead to significantly reduced fossil fuel consumption and reduced pollutant generation.

Predicting obstetric anal sphincter injuries in a modern obstetric population

A care bundle to prevent obstetric anal sphincter injuries (OASIS), including manual perineal protection, was launched in Norway in 2005. The study objective was to determine the secular trends of recurrent OASIS in second vaginal birth between 1999 and 2022. OASIS incidence among women without previous OASIS was analyzed for comparison. Data for this cohort study were obtained from the Medical Birth Registry of Norway. The study included 297,190 women with singleton pregnancies and two vaginal births during the study period. The outcome was OASIS incidence at second vaginal birth, separately for women with a history of OASIS (recurrent OASIS) and those without. To study the contribution of episiotomy, epidural analgesia, birth mode, birthweight, and maternal age to the secular trends of OASIS, logistic regression analyses with crude and adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were determined. Of the women with OASIS in their first vaginal birth, 5.4% (609 of 11,205) experienced recurrent OASIS in their second vaginal birth. The incidence of recurrent OASIS decreased from 7.7% in 1999-2002 to 3.5% in 2019-2022, representing a 51% reduction (95% CI 27-67%). Among women without previous OASIS, the OASIS incidence decreased from 1.6% in 1999-2002 to 0.6% in 2019-2022. Obstetric interventions or birthweight did not contribute to these reductions. The incidence of recurrent OASIS halved in second vaginal births among women with a previous OASIS. This reduction is likely explained by the national care bundle to reduce OASIS, launched in Norway in 2005.

Obstetric anal sphincter injuries in spontaneous vaginal births in nulliparous pregnant individuals: a 21-year cohort study based on real-world data.

Please cite this paper as: Baghestan E, Irgens L, Bordahl P, Rasmussen S. Risk of recurrence and subsequent delivery after obstetric anal sphincter injuries. BJOG 2012;119:62–69. Objective To investigate the recurrence risk, the likelihood of having further deliveries and mode of delivery after third to fourth degree obstetric anal sphincter injuries (OASIS). Design Population-based cohort study. Setting The Medical Birth Registry of Norway. Population A cohort of 828 864 mothers with singleton, vertex-presenting infants, weighing 500 g or more, during the period 1967–2004. Methods Comparison of women with and without a history of OASIS with respect to the occurrence of OASIS, subsequent delivery rate and planned caesarean rate. Main outcome measures OASIS in second and third deliveries, subsequent delivery rate and mode of delivery. Results Adjusted odds ratios of the recurrence of OASIS in women with a history of OASIS in the first, and in both the first and second deliveries, were 4.2 (95% CI 3.9–4.5; 5.6%) and 10.6 (95% CI 6.2–18.1; 9.5%), respectively, relative to women without a history of OASIS. Instrumental deliveries, in particular forceps deliveries, birthweights of 3500 g or more and large maternity units were associated with a recurrence of OASIS. Instrumental delivery did not further increase the excess recurrence risk associated with high birthweight. A man who fathered a child whose delivery was complicated by OASIS was more likely to father another child whose delivery was complicated by OASIS in another woman who gave birth in the same maternity unit (adjusted OR 2.1; 95% CI 1.2–3.7; 5.6%). However, if the deliveries took place in different maternity units, the recurrence risk was not significantly increased (OR 1.3; 95% CI 0.8–2.1; 4.4%). The subsequent delivery rate was not different in women with and without previous OASIS, whereas women with a previous OASIS were more often scheduled to caesarean delivery. Conclusion Recurrence risks in second and third deliveries were high. A history of OASIS had little or no impact on the rates of subsequent deliveries. Women with previous OASIS were delivered more frequently by planned caesarean delivery.

Risk of obstetric anal sphincter injuries (OASIS) and anal incontinence: A meta-analysis

Temporal trends in the incidence of and associations between the risk factors for obstetrical anal sphincter injuries

To identify risk factors for obstetric anal sphincter injuries (OASIS) for primiparous women who gave birth vaginally and to compare recovery by OASIS status in three domains as follows: (1) physical health and functioning, (2) mental health, and (3) healthcare utilization. This secondary analysis used data from 2,013 vaginal births in the First Baby Study, a prospective cohort study of women with first births between 2009 and 2011. Interview data at multiple time points were linked to birth certificate and hospital discharge data. The key exposure of interest was OASIS (3rd or 4th degree perineal laceration, identified in the hospital discharge data; n = 174) versus no OASIS (n = 1,839). We used multivariable logistic regression models to examine the association between OASIS and a range of outcomes including physical health and functioning, depression, and health care utilization, assessed at 1 month and 6 months postpartum. Eight percent of women had OASIS. In adjusted models, there were no differences in general physical health and functioning measures by OASIS (such as fatigue and overall self-rated health), but women with OASIS had higher rates of reporting perineal pain (p < 0.001), accidental stool loss (p = 0.001), and bowel problems (p < 0.001) at 1-month postpartum. By 6-month postpartum, there were no differences in reported physical health and functioning. There were no differences in probable depression at 1- or 6-month postpartum. Women with OASIS were more likely to attend a comprehensive postpartum visit, but there were no other differences in health care utilization by OASIS. Women with OASIS were at increased risk of accidental stool loss, bowel problems, and perineal pain in the immediate postpartum period. Women who had OASIS had similar physical functioning across a range of general health outcomes to women who gave birth vaginally without OASIS. · Higher risk of bowel problems and accidental stool loss 1-month postpartum with OASIS.. · Higher risk of perineal pain 1-month postpartum with OASIS.. · No differences in health outcomes at 6-months postpartum by OASIS..

INTRODUCTION: Obstetric anal sphincter injuries (OASIS) are a significant complication of vaginal deliveries. Asian race is a known independent predictor of perineal trauma. Limited data demonstrate a plausible explanation of this racial disparity. We aim to assess the relationship between the fetal maternal size disproportion as measured by fetal birth weight to prepregnancy BMI ratio (BW:BMI) and OASIS in mothers of different race groups. METHODS: Retrospective cohort study of vaginal deliveries between 2006 and 2015. Demographics and obstetrical data were abstracted and compared. The significance of BW:BMI to OASIS was evaluated. Results adjusted for confounding factors. RESULTS: 16,024 vaginal deliveries were included. 28.5% had no lacerations, 64.6% had 1st or 2nd degree lacerations, and 6.9% had OASIS. Demographic factors associated with OASIS included Asian race, nulliparity, increased age, increased birth weight, episiotomy, trial of labor after cesarean, and operative vaginal deliveries. Although BMI was not an independent risk factor, BW:BMI showed a significant relationship with OASIS. For every 10 unit increase in BW:BMI, the adjusted odds of having an OASIS increased by 16% (p= &lt; .001). After adjusting for BW:BMI, Asian race had higher OASIS rates. Interaction between race groups and BW:BMI was only significant for 1st and 2nd degree lacerations, not OASIS. CONCLUSION: This study verified known risk factors associated with OASIS. Increasing BW:BMI is associated with OASIS. However, BW:BMI does not provide insight into OASIS racial disparities; further investigations are needed to understand why Asian race is an OASIS risk factor.