Obstetric Perineal Tears in Pregnant Adolescents and the Influencing Factors.

Study Objective: The incidence and risk factors of obstetric perineal tear occurrence in vaginal delivery of adolescent pregnant patients are not well established. We aimed to describe the incidence of obstetric perineal tears in adolescents and the maternal obstetric risk factors associated with this situation.

Design: Retrospective cohort study SETTING: Department of Obstetrics and Gynecology, Tepecik Education and Research Hospital, Izmir, Turkey PARTICIPANTS: Adolescent pregnant patients (≤19 years) who delivered vaginally in our institution between January 2014 and January 2021 INTERVENTIONS AND MAIN OUTCOME MEASURES: The main outcome measures were the incidence of perineal tears, the degree of perineal tears, and the risk factors associated with severe perineal tears in adolescents. Severe perineal tears include third- and fourth-degree lacerations. A third-degree tear is defined as partial or complete disruption of the anal sphincter muscles, and a fourth-degree tear is defined as lacerations involving the rectal mucosa.

Results: A total of 3441 adolescents who had a vaginal delivery were included in the study. The rate of severe perineal tear was 5.8% (200/3441). Risk factors associated with obstetric laceration in adolescents in multivariate analysis were nulliparity (OR = 1.72; 95% CI, 1.14-2.41; P = 0.007), high birth weight (OR = 4.1; 95% CI, 2.71-6.21; P < 0.001), and labor induction (OR = 1.36; 95% CI, 1.01-1.85; P = 0.02). Spontaneous onset of labor and previous delivery reduced the risk of severe perineal tear in adolescent pregnant patients (respectively, OR = 0.68; 95% CI, 0.51-0.94; P = 0.02 and OR = 0.51; 95% CI, 0.33-0.79; P = 0.007).

Conclusions: In adolescents, the risk of severe perineal tear was associated with nulliparity, birth weight, and labor induction. The only possible modifiable risk factor was labor induction.