Journal Article

Factors associated with normal physiological birth for women who labor in water: A secondary analysis of a prospective observational study


Introduction. Research to understand factors associated with normal physiological birth (unassisted vaginal birth, spontaneous labor onset without epidural, spinal or general anaesthetic, without episiotomy) is required. Laboring and/or giving birth in water has been shown to be associated with a high proportion of physiologic birth, but with little understanding of factors which may influence this outcome. This study explored factors associated with normal physiological birth for women who labored in water. Methods. We conducted a secondary analysis of a UK-based prospective observational study of 8,064 women at low risk of childbirth complications who labored in water. Consecutive women were recruited from birth settings in England, Scotland, and Northern Ireland. Planned place of birth, maternal characteristics, intrapartum events, maternal and neonatal outcomes were measured. Univariable and multivariable logistic regression modelling explored factors associated with normal physiological birth. Results. In total, 5758 (71.4%) of women who labored in water had a normal physiological birth. Planned birth in the community [aOR 2.58, 95% CI 2.22-2.99] or at an alongside midwifery unit [aOR 1.21, 95% CI 1.04-1.41] was positively associated with normal physiological birth compared with planned birth in an obstetric unit. Duration of second stage [aOR 0.66, 95% CI 0.62–0.70], duration in the pool [aOR 0.93, 95% CI 0.90–0.96] and birth weight of the neonate [aOR 0.74, 95% CI 0.65–0.85] were negatively associated with normal physiological birth. Parity was not associated with normal physiological birth in multivariate analyses. Discussion. Our findings largely reflected wider research, both in and out of water. We found midwifery-led birth settings may increase the likelihood of normal physiological birth among healthy women who labor in water, irrespective of parity. This association supports growing evidence demonstrating the importance of planned place of birth on reducing intervention rates, and adds to research on labor and birth in water.

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Carpenter, Jane
Burns, Ethel
Smith, Lesley

Oxford Brookes departments

Oxford School of Nursing and Midwifery


Year of publication: 2022
Date of RADAR deposit: 2021-10-19

Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License

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