Abstract

Objective Instrumental vaginal delivery is associated with birth trauma to infant and obstetric trauma to mother. As caesarean delivery rates increased during the past decades, the rate of instrumental vaginal delivery declined. We examined concomitant temporal changes in the rates of severe birth trauma and maternal obstetric trauma. Design A retrospective observational study. Settings and participants All hospital singleton live births in Washington State, USA, 2004–2013, excluding breech delivery. Severe birth trauma (brain, nerve injury, fractures and other severe birth trauma) and obstetric trauma (third/fourth degree perineal lacerations, cervical/high vaginal lacerations) were identified from hospitalisation data. Pregnancy and delivery characteristics were obtained from birth certificates. Temporal trends were assessed by the Cochran-Armitage test. Logistic regression was used to obtain adjusted ORs (AORs) and 95% CI. Results Overall, 732 818 live births were included. The rate of severe birth trauma declined from 5.3 in 2004 to 4.5 per 1000 live births in 2013 (P<0.001). The decline was observed only in spontaneous vaginal delivery, the rates of fractures and other severe birth trauma declined by 5% and 4% per year, respectively (AOR: 0.95, 95% CI 0.94 to 0.97 and AOR: 0.96, 95% CI 0.93 to 0.99; respectively). The rate of third/fourth degree lacerations declined in spontaneous vaginal delivery from 3.5% to 2.3% (AOR: 0.95; 95% CI 0.94 to 0.95) and in vacuum delivery from 17.3% to 14.5% (AOR: 0.97, 95% CI 0.96 to 0.98). Among women with forceps delivery, these rates declined from 29.8% to 23.4% (AOR: 0.98, 95% CI 0.96 to 1.00). Conclusion While the rates of fractures and other birth trauma declined among infants delivered by spontaneous vaginal delivery, the rate of birth trauma remained unchanged in instrumental vaginal delivery and caesarean delivery. Among mothers, the rates of severe perineal lacerations declined, except for women with forceps delivery.