Objective: To determine if variation exists between ethnicities for risk of perineal, vaginal, and cervical laceration at vaginal delivery.
Study design: Retrospective cohort study of nulliparous women who underwent vaginal delivery of a vertex presentation. Predictor variable was ethnicity with outcome variables cervical, vaginal, and second-, third-, or fourth-degree perineal laceration. Logistic regression analysis was conducted to control for confounders.
Results: Of the 17,216 who met criteria, Filipino (OR = 1.92, 95% CI 1.64-2.25) and Chinese (OR = 1.60, 95% CI 1.33-1.92) women were at greatest risk for third- and fourth-degree laceration. Only Filipino (OR = 1.32, 95% CI 1.10-1.57) and other Asian (OR = 1.23, 95% CI 1.08-1.41) women were at slightly increased risk of vaginal laceration. No differences were seen for cervical laceration.
Conclusion: Different ethnicities are at widely varying risk of perineal laceration, but little difference exists for vaginal or cervical lacerations. Research into the mechanisms behind this should investigate differences in perineal anatomy.