New POOL study establishes safety of waterbirths for women with an uncomplicated pregnancy

Women with experiences of waterbirths in Wales have praised new research confirming that among women with an uncomplicated pregnancy and labour who use water immersion during labour, giving birth in water does not increase risks for mothers or their babies.

While some mothers use water for pain relief, some doctors had expressed concern that babies could become seriously ill after waterbirths, and that mothers may be more likely to have severe tears or heavy blood loss.

The POOL study, led by Cardiff University’s School of Healthcare Sciences and Centre for Trials Research, studied NHS records from 87,040 women who used a pool in labour between 2015 and 2022, across 26 NHS organisations in England and Wales. The researchers looked at rates of severe tears experienced by women, rates of babies needing antibiotics or help with breathing on a neonatal unit, as well as mortality rates in newborn babies.

The study – funded by the National Institute for Health and Care Research (NIHR), with specific contributions from Health and Care Research Wales via the Health Technology Assessment (HTA) programme, was designed to find out if staying in the water to give birth is as safe for mothers and their babies as leaving the water before birth.  In Wales, the study was hosted at Cardiff and Vale University Health Board, which was also the only health board using the industry partnered maternity information system EuroKing, which holds all maternity records and data at the Health Board.

Heledd Williams, 32, from Cardiff, elected to have a waterbirth at the Heath Hospital’s Midwife Led Unit (MLU) six months ago due to her anxiety about giving birth.

She said: “It sounds silly but giving birth was the bit I was afraid of - I knew I wanted to have children, but I’m not very good with blood and medical stuff!

“I'd read a book about waterbirths and that intrigued me - I really enjoy being in the water, so I thought I’d look more into it and I had a chat with my midwife about the pros and cons, which suggested there were far more upsides to waterbirth than downsides.

“My husband mentioned the change in my face as soon as I went into the water – it was just pure relief, and it just felt as natural as possible. It was a really viable option in terms of helping me to manage the pain - it just relaxed me.

“I think the research into this is really important and it’s good to know that research is being done in this area.” 

 Professor Julia Sanders, Health and Care Research Wales Speciality Lead for Reproductive Health and a Professor of Clinical Midwifery, who led the research team, added: “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 waterbirths could carry extra risks. There have been reports that babies could become seriously ill, after waterbirths, and that mothers were more likely to have severe tears or heavy blood loss. A large research study was therefore needed to look at the safety of waterbirths in the UK.

“The main aim of our study was to answer a question commonly asked by women using birthing pools or baths during labour - midwives are often asked by mothers if they should stay in or leave the water to give birth if labour remains uncomplicated.

“In the women we studied, some left the pool for extra medical care or more pain relief. Most of the women who got out of the pool for extra medical care were first time mothers - 1 in 3 first time mothers got out of the pool for extra medical care, compared to 1 in 20 of the women who had previously given birth.”

‘Implications for thousands of women a year in the UK’

Overall, the researchers found that around half of all women who used a pool in labour had a waterbirth.

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.

Rachel Plachcinski, a parent representative on the study team and former antenatal teacher, added: “It’s also reassuring to see that midwives are picking up potential problems during labour and advising those women to leave the pool, so mothers and their babies can receive appropriate monitoring and care.”

The research, ‘Maternal and neonatal outcomes among spontaneous vaginal births occurring in or out of water following intrapartum water immersion: The POOL cohort study,’ was published in BJOG, the official academic research journal of the Royal College of Obstetricians and Gynaecologists. Visit the Cardiff University website to find out more about the study.

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