Water Birth and Perinatal Outcomes in British Columbia: A Retrospective Cohort Study.

Abstract

This study aimed to quantify adverse neonatal outcomes in a cohort of registered midwife (RM)-attended conventional and water births in British Columbia. The study included all term singleton births in British Columbia between January 1, 2005 and March 31, 2016 attended by RMs. Births were allocated to a conventional birth cohort or a water birth cohort according to where the actual birth of the neonate took place. The primary outcome was a composite adverse neonatal outcome (Apgar <7 at 5 minutes, resuscitation need, neonatal intensive care unit admission). Secondary outcomes included individual components of the primary outcome, maternal length of labour, and degree of perineal laceration (Canadian Task Force Classification Level II-2). The population included 25798 births. Of these, 23201 were conventional, and 2567 were water births. The rate of the composite adverse neonatal outcome was not higher in water births compared with conventional births (hospital conventional, 5.0%; hospital water, 4.2%; home conventional, 3.4%; and home water, 2.9%). Rates of individual components of the composite adverse neonatal score were not greater in the water birth cohort. Maternal outcomes included statistically shorter labours in the water birth cohort and no difference between the cohorts in incidence of third- and fourth-degree lacerations. Water births attended by RMs in British Columbia are not associated with higher rates of adverse neonatal outcomes than conventional births attended by midwives.