Giving birth in a water bath does not increase the risk of complications for the baby or its mother, a study has found.

Researchers at the University of Cardiff assessed 73,229 records from low-risk pregnancies where a water pool was used during labour across 26 NHS organisations in England and Wales between 2015 and 2022.

The analysis looked at the rate of severe tears experienced by the women who gave birth, alongside the number of babies who needed antibiotics or help with their breathing on the neonatal ward and the number of babies who had died during birth.

The risks to the babies and their mothers were no higher among water births compared with births out of water, the researchers concluded.

Water births make up about 9% of the almost 600,000 births on the NHS each year. Under clinical guidelines, all expectant mothers should be offered water births as an option for delivery.

Julia Sanders, a professor of clinical midwifery at Cardiff University who led the research, said the research showed water births were a safe alternative to births outside of water. “In the UK around 60,000 women a year use a birth pool or bath for pain relief in labour, but some midwives and doctors were concerned that water births could carry extra risks,’” she said.

“There have been reports that babies could become seriously ill or even die after water births, and that mothers were more likely to have severe tears or heavy blood loss. We wanted to establish if water births with NHS midwives are as safe as giving birth out of water for women and their babies at low risk of complications.”

Peter Brocklehurst, emeritus professor of women’s health at the Birmingham Clinical Trials Unit, said: “Given that 10% of women use immersion in water as pain relief in labour, the results of this study will have implications for thousands of women a year in the UK and many more around the world, where immersion in water during labour is common practice.”

Prof Chris Gale, a consultant neonatologist at Chelsea and Westminster NHS Foundation Trust in London, said: “Many paediatricians and neonatologists worry that births in water might carry extra risks for babies, but the study found convincing evidence that for women with an uncomplicated pregnancy this is not the case.”