RESUMO
Objectives: To estimate the prevalence and risk factors for obstetric anal sphincter injuries [OASIS] in Saudi Arabia using data in a tertiary care University Center
Design: A retrospective case-control study
Setting: King Khalid University Hospital, Kingdom of Saudi Arabia
Subjects: All women with third and fourth degree perineal tears over a 10-year period
Interventions: We conducted this study by creating an obstetric database compiled over a period of 10 years [2002-2012] screening all for third and fourth degree perineal tears and too control matched by the time of delivery and delivery team [midwife and obstetrician]
Main Outcome Measures: The prevalence of perineal injuries was calculated in cases and controls. Maternal and obstetric parameters were analyzed and compared between the two groups
Results: Of 31,665 vaginal deliveries, seventy-three patients [0.23 %, 95% Cl by the adjusted wald method: 0.18%-0.29%] had a recognized third [n=66] or fourth-degree [n=7] perineal tear. The following three variables were independently associated with OASIS on multivariate logistic regression models adjusting for potential confounders: primiparity [OR 3.32] instrumental delivery [OR 7.19] and episiotomy [OR 4.92]
Conclusion: The overall prevalence of third- and fourth-degree perineal tears in our population is low; avoidance of certain obstetric interventions including instrumental delivery and episiotomy may decrease such complications