Why Are Hot Tubs Bad for Pregnancy? What You Need to Know

Craving a soak while pregnant? Hold that towel! Hot tubs are risky during pregnancy because high heat can harm your baby’s development—especially early on. Want the steamy details (and safe alternatives)? Keep reading! Hot Tubs can wait—your baby’s safety comes first.

Hot Tubs and Pregnancy – Understanding the Risks

Picture this: you're eight weeks pregnant, your back’s aching, and all you want is to melt into a bubbling hot tub. Bliss, right? Maybe not.

While hot tubs, saunas, jacuzzis and steam rooms sound like heaven, they can cause more harm than good when you’re expecting—especially in those early weeks. It’s not just about comfort. It’s about core temperature, baby development, and keeping things safe.

Let’s dive into the warm (but not too warm) truth behind hot tubs and pregnancy.

The Science Behind the Risks: Hyperthermia and Fetal Development

What is Hyperthermia?

Hyperthermia isn’t just a fancy medical term—it’s what happens when your body overheats. Think of it like your internal thermostat going rogue, pushing your temperature above 38.9°C.

Now, during pregnancy, your baby can’t cool down the way you can. If you’re too warm for too long, they’re right there with you—feeling the heat. And that’s where problems can start.

Neural Tube Defects: A Primary Concern

One of the biggest worries? Neural tube defects, or NTDs. These are serious conditions like spina bifida and anencephaly, affecting the spine and brain.

The first 6 to 7 weeks of pregnancy are when the baby’s brain and spine begin to form. Sadly, this is also when overheating can increase the risk of things going wrong. Studies have shown that using hot tubs during this delicate window may be linked to a higher chance of NTDs.

It doesn’t take much—a few minutes too hot can be all it takes.

Other Potential Risks

Overheating isn’t the only red flag. You might also face:

• Dehydration – Heat makes you sweat more, meaning you lose fluids faster.

• Dizziness and fainting – Your blood pressure is already lower in pregnancy. Add heat, and you might feel woozy.

• Reduced blood flow to your baby – Your body focuses on cooling you, not nourishing your womb.

• Miscarriage risk – Some studies suggest a possible link, though more research is still needed.

It all adds up to one thing: caution is key.

Temperature Matters: How Hot is Too Hot?

Safe Temperature Guidelines

Let’s talk numbers. Experts recommend keeping water no hotter than 37–38°C during pregnancy. Sounds warm enough, right?

The danger zone begins at 39°C and above. That’s when your body can start struggling to cool itself. And since hot tubs often hover between 37.5°C and 40°C, you can see why things get risky quickly.

Time Limits: How Long is Too Long?

Even if the water feels just right, don’t linger. Ten minutes or less—that’s your safe zone.

Hot tubs keep their heat constant, unlike a bath that cools over time. The longer you sit in, the more your core temperature rises. That’s why time matters just as much as temperature.

First Trimester: The Highest Risk Period

Why the First Trimester is Critical

The first trimester is like your baby’s blueprint phase. Organs, spine, and the entire nervous system are forming at lightning speed.

Because this stage is so crucial, the baby is more sensitive to external stress—like heat. That’s why most healthcare professionals will gently but firmly suggest avoiding hot tubs during these early weeks.

Better safe than sorry, especially when everything’s just beginning.

Alternatives to Hot Tubs in the First Trimester

Missing that warm hug of bubbles? You’re not alone. But there are safer ways to unwind.

Try a warm bath instead—one where your chest stays above the water. A foot soak with Epsom salts can be surprisingly relaxing. Or treat yourself to a prenatal massage—bliss without the burn.

Hot Tub Safety: Precautions and Recommendations

Safe Hot Tub Practices (If Use is Desired)

Still tempted to dip in? Here’s how to do it a little more safely:

• Keep the temp under 37.5°C

• Soak for 10 minutes or less

• Avoid the jets, especially the hot ones

• Keep your upper body above water

• Drink water to stay hydrated

• Skip it completely if you’ve got a fever

These aren’t foolproof, but they’re better than going in blind.

Hot Tub Hygiene: Reducing Germ Exposure

It’s not just about heat—germs love hot tubs, too. Especially public ones.

Warm, bubbly water makes a lovely home for bacteria like Pseudomonas, which can cause skin rashes or worse. If you’re using a tub at home, maintenance is a must.

Make sure:

• The chlorine and pH levels are right

• The filter’s clean

• You change the water regularly

Because warm and dirty? No thanks.

What About Baths, Showers, and Other Heat Sources?

Bath Safety

A warm bath is a brilliant alternative. Unlike hot tubs, they naturally cool over time, which helps you keep your body temperature in check.

Just don’t go steaming hot. And if in doubt, keep your chest and shoulders above water—simple and safe.

Shower Safety

A hot shower feels amazing, but too much steam can sneak up on you. If you start feeling flushed or dizzy, it's time to step out.

Keep showers short and sweet, and avoid blasting hot water on your belly.

Other Heat Sources to Avoid

Heat hides in the sneakiest places. During pregnancy, be wary of:

• Saunas and steam rooms

• Electric blankets or heated mattress toppers

• Sitting out in the blazing sun too long

If your body’s shouting, “I’m too hot!”—listen to it.

When to Consult Your Doctor

Pregnancy isn’t one-size-fits-all. What’s risky for one person might be less so for another.

So before you jump into anything heat-related, have a chat with your GP or midwife. They’ll help you weigh up the pros and cons, based on your specific needs.

Your peace of mind is worth it.

Conclusion: Making Informed Choices for a Healthy Pregnancy

There’s no denying that hot tubs are tempting. But when you’re pregnant—especially in those early months—it's best to skip the soak.

The good news? There are plenty of safe ways to unwind without turning up the heat. A bit of planning and a splash of caution now can make all the difference.

And once baby’s here? That bubbly soak will feel even more rewarding.