Severe perineal trauma among women undergoing vaginal birth after cesarean delivery: A population‐based cohort study

Abstract

Background To examine risk of severe perineal trauma among nulliparous women and those undergoing vaginal birth after cesarean delivery (VBAC). Methods This is a population‐based cohort study of all births to women with their two first consecutive singleton pregnancies in Stockholm‐Gotland Sweden between 2008 and 2014. Risk of severe perineal trauma was compared between nulliparous women and those undergoing VBAC with severe perineal trauma being the main outcome measure. Associations between indication and timing of primary cesarean delivery and risk of severe perineal trauma in subsequent vaginal birth were analyzed using Poisson regression analysis. Results The rate of severe perineal trauma among nulliparous women and those undergoing VBAC was 7.0% and 12.3%, respectively. Compared with nulliparous women, those undergoing VBAC were significantly older, had a shorter stature, and gave birth in a non‐upright position to heavier infants with larger head circumferences. The rate of instrumental vaginal delivery among nulliparous women and those undergoing VBAC was 19.3% and 20.2%, respectively (P = 0.331). An increased risk of severe perineal trauma remained after adjustments among those undergoing VBAC (adjusted risk ratio 1.42, 95% CI 1.23‐1.63). Level of risk was not associated with indication (dystocia or signs of fetal distress) of primary cesarean delivery, nor how far the woman had progressed in labor (fully dilated versus planned cesarean delivery) before delivering by cesarean. Conclusions Compared with nulliparous women, those undergoing VBAC are at increased risk of severe perineal trauma, irrespective of indication and timing of primary cesarean delivery.

A step towards better audit: The Robson Ten Group classification system for outcomes other than cesarean section

“…In women with a previous CS, there was a lower OASIS rate after induced labor than after spontaneous onset. In contrast to previous studies, this observation is based on attempted vaginal births after previous CS, not achieved vaginal births 27–30 . The PPH rate was higher in term cephalic singleton births by prelabor CS than in spontaneous or induced labor for both nulliparous and multiparous women with unscarred uterus.…”

“…In contrast to previous studies, this observation is based on attempted vaginal births after previous CS, not achieved vaginal births. [27][28][29][30] The PPH rate was higher in term cephalic singleton births by prelabor CS than in spontaneous or induced labor for both nulliparous and multiparous women with unscarred uterus. Furthermore, spontaneous onset of labor was associated with lower proportions of Apgar score <7 at 5 minutes compared with prelabor CS, which challenges the belief that prelabor CS is a shortcut to better neonatal health.…”

One Plus One Equals Two—will that do? A trial protocol for a Swedish multicentre randomised controlled trial to evaluate a clinical practice to reduce severe perineal trauma

“…Other complications of severe perineal trauma are pain [ 3 ], dyspareunia [ 4 ], an altered body image, and psychosocial problems [ 5 – 7 ]. Risk factors for severe perineal trauma are giving birth vaginally for the first time, having an assisted vaginal birth, giving birth vaginally after a previous caesarean section, or giving birth to a baby that weighs more than 4000 g, ethnicity, and the risk increases with age [ 8 – 11 ]. Some of the methods used to prevent perineal injuries have been evaluated in clinical trials, but there are still gaps in the evidence [ 12 ].…”

Risk of obstetric anal sphincter injury among women who birth vaginally after a prior caesarean section: A state-wide cohort study

“…However, compared with vaginal birth in primiparous women, there is emerging evidence suggesting successful VBAC is also associated with an increased risk of obstetric anal sphincter injury (9,10,15). Past studies in this field have been limited by small cohort sizes, lack of broader generalisability (limited to a single hospital cohort) or outdated methodology (such as a reliance on complete case records only, which may lead to ascertainment bias) (16).…”

“…Prior studies have consistently suggested that women having a VBAC are up to 1.4-fold more likely to sustain significant perineal injury compared with their primiparous counterparts (8,9,15). And yet, the risk of perineal injury is still only peripherally acknowledged in many professional guidelines (17,18) and is not routinely included in antenatal counselling of women considering a VBAC.…”