Seven reasons to question restrictions on birth pools for women with a higher BMI

My research on this area consistently shows that the things that women with a higher BMI are told are often not evidence-based.

Weight bias is a significant problem in maternity care, and women with a higher BMI experience stigma, often finding that they are denied the things that can make a positive difference to their experience.

Like birth pools.

For example, in 2026, an Australian study looked at larger-bodied women’s experiences trying to access water immersion for labour and birth and confirmed that:

“BMI-based restrictions and inconsistent clinical practices undermine autonomy and equitable access to the effective pain relief offered through water immersion for labour and birth. Women reported emotional distress, reduced trust in care, and challenges self-advocating in a system that often pathologises their larger bodies.” (Mackinnon et al 2026)

The benefits are clear

In fact, the benefits of water immersion in labour are well-established, and many of the reasons given for placing restrictions on birth pools don’t stand up to scrutiny.

That’s the case for all women, in fact, not just those with a higher BMI.

So some of the information in this blog post might help you even if you don’t have a higher BMI.

1. Water immersion is safe and beneficial for most women

“We have evidence from research into tens of thousands of births that using water for labour and birth is safe for both mother and baby, and that it leads to good outcomes with fewer interventions.” (Wickham 2023).

Women with a higher BMI can benefit just as much—if not more—from the pain relief, improved mobility, and greater satisfaction associated with water use in labour.

Restrictions on birth pools mean that women aren’t able to access something that might truly help them.

That alone is justification to question them.

2. Being plus size doesn’t mean you can’t move

“Many of us are just as capable of moving around as women with a lower BMI, and sometimes more so.” (Wickham 2023).

Water provides buoyancy, which can help with ease of movement in labour—something that can be particularly useful for larger-bodied people.

But it is inappropriate to make assumptions about someone’s mobility based on their size or shape.

3. The chance of fainting in a pool is extremely low

Some caregivers and institutions cite the chance of fainting as a reason to not let larger women use birth pools. They claim that, if a woman felt woozy, or fainted, it might be difficult to get her out of the pool, because of her shape or size.

However, as I wrote in my Plus Size Pregnancy book:

“The vast majority of women do not pass out in a birthing pool. In fact, Consultant Midwife Julie Frohlich and I worked out the approximate chance of a woman feeling faint and needing help to get out of a birth pool, based on data from a large London hospital.

It turns out that, over the past few years, this has happened in less than 1 in 1000 labours, based on all women, not just those who have a higher BMI. I have since compared data with several other senior midwives, with similar results. None of us are aware of any incident of a woman with a higher BMI having collapsed in a birth pool.

One might think, from listening to people talk about this risk, that women with a high BMI are going around regularly fainting in birth pools like Jane Austen heroines. In fact, larger women may even be less likely to do this than women with a ‘normal’ or low BMI, because of the obesity paradox and our increased blood volume and other reserves.

We also need to remember that labouring women are sane, intelligent people who do not wish to faint in a water pool any more than their caregivers wish for them to do so.” (Wickham 2023).

In summary, there’s no evidence that women with higher BMI are more likely to faint in the pool. In fact, due to the ‘obesity paradox’, larger women may have more physiological reserves.

What you could say to caregivers:

“I’ve read that fainting in birth pools is very rare, and I’ll let you know straight away if I feel lightheaded. I’ll also take steps to stay hydrated and avoid overheating.”

4. There are practical solutions if someone does need help out of the pool

“It is indeed true that midwives may not be able to lift you out of a pool, but the majority of midwives probably couldn’t lift an eight stone (50kg) woman out of a pool without help, and if they need help or equipment to help a woman with a lower BMI then why can’t the same equipment be used for women with a higher BMI?

I am again not underplaying the fact that we need to protect midwives from injury, but other things that can be done include draining the water or, in the extremely unlikely event that every other idea fails, someone can support your head above the water while further help is called.

This situation is so unlikely, however, that none of the practitioners I spoke to while writing this book, who have between them spent many years working in hospitals and birthing units which see tens of thousands of births each year, had even heard of this having ever happened.

In the very small number of cases that people knew of where plus size women needed to get out of a pool quickly, this happened safely and successfully.” (Wickham 2023).

What you could say to caregivers:

“If a rare emergency arises, what would you do for someone with a lower BMI in the same situation? Could those steps not also be taken for me?”

5. Weight and BMI are not the same—and BMI alone is a blunt tool

“A very short woman with a BMI of 40 can easily weigh less than a very tall woman with a BMI considered acceptable for birth pool use.”

Some units use weight limits instead of BMI, but both approaches can be arbitrary and don’t account for individual strength, mobility, or health.

What you could say to caregivers:

“Is your policy based on BMI, weight, or something else? Could we look at my individual situation rather than applying a blanket rule?”

6. It’s unequal and discriminatory to make larger women prove themselves

“Sometimes, hospitals or birth centres ask larger women to ‘prove’ that they can get in and out of the birth pool, by demonstrating this to them in late pregnancy. This is really not okay, because women whose BMI is lower are not asked to prove that they can do this, and there is no direct correlation between BMI or weight and fitness or mobility, but some women are happy to do it because they see it as the fastest way to be ‘allowed’ to use the pool.” (Wickham 2023).

Requiring only plus size women to demonstrate they can get in and out of a pool is a double standard and perpetuates stigma.

7. It’s not about size—it’s about systemic assumptions

“Getting anybody out of the bath if they’re unconscious and a dead weight is a challenge. It doesn’t matter if they have a high BMI or not. It’s just an excuse, it’s about following the system.” (Zoe, midwife). (Wickham 2023).

All of the reasons that are given to women to explain restrictions on birth pools are questionable.

The concern is less about a woman’s actual size or health status and more about stigma, fear, and weight bias in systems of care that don’t account for individual needs.

What you could say to caregivers:

“It sounds like the concern is more about systems and protocols than individual risk. Could we work together to make a plan that supports my preferences and your responsibilities?”

In Summary

The evidence shows that water immersion can be a safe and effective option for women of all sizes.

Restrictions on birth pools based on BMI alone are not only unsupported by evidence but can also perpetuate unequal treatment and stigma.

Every woman deserves to make informed decisions about her labour and birth options, based on individual needs rather than blanket policies.

You can find more information, references, and support for making informed choices in my book:
Plus Size Pregnancy: what the evidence really says about higher BMI and birth.

And I have more tips on how to determine what you need, and get the care that’s right for you in What’s Right For Me? Making decisions in pregnancy and childbirth.

Plus Size Pregnancy

What’s Right For Me?

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Books to help you become informed and make the decisions that are right for you…

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