Abstract
Introduction and hypothesis The aim of this study was to
assess the occurrence of severe perineal lacerations in vaginal
delivery and its relationship with predisposing clinical and
obstetric factors.
Methods A retrospective cohort analysis using an electronic
clinical database at a University Referral Center for high-risk
pregnancies was performed. A total of 941 vaginal deliveries
were analyzed, over 10 consecutive months in 2013 and 2014.
The relationship between obstetric and clinical characteristics
and lacerations, especially severe forms, was analyzed. The
frequency and severity of birth canal lacerations were compiled
and classified as mild (unintentional laceration grades I
and II, and mediolateral episiotomy) and severe (grades III
and IV). The crude and adjusted odds ratios and 95 % confidence
intervals were estimated in univariate and multivariate
logistic regression models.
Results The overall incidence of perineal lacerations in vaginal
delivery was 78.2 % (n=731). Lacerations were considered
mild in 708 women (75.7 %) and severe in 23 women
(2.5 %). Maternal age, parity, use of forceps, mediolateral
episiotomy, and birth weight influenced the occurrence of
some degree of tear. The chance of severe lacerations increased
1.77-fold per week with the gestational age (1.03–
3.03, P=0.025), while primiparity increased the chance of
laceration 5.32-fold. Episiotomy did not show a protective
effect against severe laceration occurrence (P=0.999).
Conclusions Severe perineal lacerations were associated with
operative delivery, primiparity, gestational age, and epidural
anesthesia. Episiotomy was not protective.
Keywords Perineal trauma . Perineal tears . E