ResearchObstetricsModifiable risk factors of obstetric anal sphincter injury in primiparous women: a population–based cohort study
Section snippets
Materials and Methods
We performed a population-based cohort study where data were retrieved from the Danish Medical Birth Registry (MBR). Primiparous women with a vaginal singleton delivery at term (fully 37 weeks of gestation) in the time period 2000-2010 (n = 214,256) were included. An OASIS was classified according to the Royal College of Obstetricians and Gynaecologists classification.24 A third-degree OASIS was defined as a partial or complete disruption of the anal sphincter muscles, which may involve only
Results
Of 214,256 women with a first vaginal delivery in 2000-2010, 13,907 (6.5%; 95% CI, 6.4–6.6%) had an OASIS. Of these, 11.5% (n = 1599) had a fourth degree OASIS. Table 1 shows distribution of the potential risk factors in women with and without OASIS. Univariable analyses (Table 2) showed that all factors included in the analysis were significant risk factors, except breech presentation, which was a significant protective factor.
We found an interaction between vacuum extraction and mediolateral
Comment
We found that mediolateral episiotomy was protective against OASIS in primiparous women, when used in deliveries assisted by vacuum extraction. We found no protective effect of mediolateral episiotomy when used without vacuum extraction, which is in accordance with some previous findings,8, 10, 13 but in contrast to other findings.5, 21, 23 Vacuum extraction without mediolateral episiotomy was an important risk factor of OASIS, which is in accordance with previous findings.5, 6, 7, 8, 9, 11, 12
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2021, American Journal of Obstetrics and Gynecology MFMCitation Excerpt :We observed a nonsignificant common risk difference in instrumental deliveries of 12%, and it remains possible that data from ongoing randomized controlled trials37,38 will contribute toward the detection of a smaller clinically significant reduction in instrumental delivery, especially rotational procedures. This is important because instrumental deliveries are associated with maternal complications, including obstetrical anal sphincter injury, levator avulsion, and postpartum hemorrhage,13,15,39,40 and perinatal complications, including subgaleal hemorrhage, intracranial hemorrhage, nerve injury, and skull fracture.41–44 The difference in episiotomies (40% in the manual rotation group vs 54% in the sham rotation group) could be because of fewer instrumental births in the manual rotation group.
Patient's characteristics and incidence of fecal incontinence after primary repair of Obstetric Anal Sphincter Injuries (OASIS) at three Indonesian tertiary hospitals in 2014–2016
2020, European Journal of Obstetrics and Gynecology and Reproductive Biology: XThe effects of a severe perineal trauma prevention program in an Australian tertiary hospital: An observational study
2020, Women and BirthCitation Excerpt :In spontaneous vaginal births the rate of episiotomy increased by 43% (16.2%–23.2%). Our study also saw an increase in episiotomy rates; by 14% in instrumental births (56.5%–62.1%) and 40% in spontaneous vaginal births (7.4%–10.4%) though our baseline rates were much lower than those reported by Mohiudin et al.18 Routine episiotomy has not been found to reduce the risk of SPT in a systematic review22 though several observational studies have demonstrated a protective effect in instrumental births.23,24 In our study of nulliparous women, factors increasing the chance of severe perineal trauma included Asian country of birth, forceps birth, neonate ≥4000 g and maternal age.
Prevention of obstetric anal sphincter injuries with perineal support and lateral episiotomy: A historical cohort study
2024, Acta Obstetricia et Gynecologica Scandinavica
The authors report no conflict of interest.
Reprints not available from the authors.
Cite this article as: Jangö H, Langhoff-Roos J, Rosthøj S, et al. Modifiable risk factors of obstetric anal sphincter injury in primiparous women: a population–based cohort study. Am J Obstet Gynecol 2014;210:59.e1-6.