Water Birth Maternal and Neonatal Outcomes Among Midwifery Clients in Alberta, Canada, from 2014 to 2017: A Retrospective Study.

OBJECTIVES: This study sought to evaluate retrospectively the maternal and neonatal outcomes of water births (WBs) managed by Registered Midwives in Alberta compared with traditional or "land" vaginal birth outcomes for clinical evidence or knowledge and to assist in health care management planning.

METHODS: This study was a retrospective cohort comparison of maternal and neonatal outcomes of WB (1716) and traditional or land birth (non-WB) (21 320) from selected low-risk maternal cohorts with spontaneous onset of labour and vaginal delivery in Alberta (2014-2017) using Alberta Perinatal Health Program data sets. Anonymized client and patient records linked the Alberta Perinatal Health Program data with inpatient Discharge Abstract Database for newborn and/or maternal personal health number (PHN/ULI) analyzed using SPSS 19.0 software (IBM Corp., Armonk, NY) (Canadian Task Force Classification II-2).

RESULTS: The WB group had fewer and less severe perineal lacerations despite increased macrosomia. The non-WB group had increased maternal factors (age <20 years, third- to fourth-degree perineal tears, excessive blood loss) and neonatal factors (Apgar scores <7 at 5 minutes and neonatal intensive care unit admission). No significant difference was identified between the birth groups for maternal age >35 years, primiparous status, maternal fever, maternal puerperal infection, maternal intensive care unit admission, low birth weight, neonatal resuscitation, and neonatal intensive care unit admission <28 days of life.

CONCLUSIONS: A low-risk maternal cohort of WBs (1716) managed by midwives had equivalent or improved neonatal outcomes compared with a low-risk maternal cohort of land or traditional births (21 320) managed by midwives and other maternity providers.