RESUMO
BACKGROUND: In 2014, the National University Hospital of Iceland (NUHI) merged a mixed-risk birth unit and a midwifery-led low-risk unit into one mixed-risk unit. Interprofessional preventative and mitigating measures were implemented since there was a known threat of cultural contamination between mixed-risk and low-risk birth environments. The aim of the study was to assess whether the NUHI's goal of protecting the rates of birth without intervention had been achieved and to support further development of labor services. METHODS: A retrospective cohort study of all women who had singleton births at NUHI birth units in two 2-year periods, 2012-2013 and 2015-2016. The primary outcome variables, birth without intervention, with or without artificial rupture of membranes (AROM), were adjusted for confounding variables using logistic regression analysis. Secondary outcome variables (individual interventions and maternal and neonatal complications) were analyzed using descriptive statistics, t test, and Chi-square test. RESULTS: The rate of births without interventions, both with and without AROM, increased significantly after the unit merger and accompanying preventative measures. The rates of AROM, oxytocin augmentation, episiotomies, and epidural analgesia decreased significantly. The rate of induction increased significantly. There were no significant differences in maternal or neonatal complication rates. CONCLUSIONS: Interprofessional preventative measures, implemented alongside a mixed-risk and low-risk birth unit merger, can increase rates of births without interventions in a mixed-risk hospital setting. However, it is necessary to maintain awareness of the possible effects of a mixed-risk birth environment on the use of childbirth interventions and examine the long-term effects of preventative measures.