INTRODUCTION: The literature describes advantages for mothers giving birth in water, but waterbirth is controversial in Sweden and has not been offered at hospitals until recently. This study aimed to describe and compare the characteristics and outcome of waterbirths with spontaneous vaginal births at the same clinics.

MATERIAL AND METHODS: A retrospective cohort study was conducted on all waterbirths at two maternity units in Sweden from March 2014 to November 2015 (n=306), and a consecutively selected comparison group of 306 women having conventional spontaneous vaginal births. Logistic regression was used to analyze the primary outcome; second-degree perineal tears.

RESULTS: Women giving birth in water had a lower risk of second-degree perineal tears (adj. OR 0.6 [95% CI 0.4-0.9]). Their labor was shorter (6:03 hrs. vs 7:52 hrs.) and there were significantly less interventions than in the comparison group; amniotomy (13.7% vs. 35.3%), internal cardiotocography (11.1% vs.56.8%), and augmentation with oxytocin (5.2% vs.31.3%). There were no differences in Apgar scores or admissions to neonatal intensive care unit. The experience of childbirth, measured with a numeric rating scale, was higher in the waterbirth group indicating a more positive birth experience. Three newborns born in water had an umbilical cord avulsion.

CONCLUSIONS: In this low-risk population, waterbirth is associated with positive effects on perineal tears, the frequency of interventions, the duration of labor and women's birth experience. Midwives handling waterbirth should be aware of the risk of umbilical cord avulsion. This article is protected by copyright. All rights reserved.