Is It Bad to Hold Your Breath During Pregnancy?

Is it bad to hold your breath during pregnancy? I ask as an underwater hockey player. I recognize playing has its risks, but is holding your breath one of them? Same with underwater photo shoots.
—Underwater and pregnant?

I had to look up underwater hockey! It seems fun.

This topic is under-researched. It’s a place where we can draw some limits on either side using what we know, but probably not answer directly.

To begin: swimming is good. There is a lot of evidence on the value of swimming — even competitive, intense swimming — during pregnancy. I wrote about heart rate in serious aerobic exercise, and the logic of that being okay ports over to this. Swimming is arguably a better pregnancy exercise than running because it’s less likely to injure your joints.

On the other hand, we have related concerns. People are often cautioned against scuba diving, although the issue there is more about decompression impacts rather than breath-holding. And we know that in the extreme, if mom doesn’t breathe, that is dangerous — if you suffocated, your baby would too.

What you are asking about here (based on some videos I watched) is breath-holding somewhere between athletic swimming and an extreme where you hold your breath until you pass out. As you hold your breath, your blood oxygen level will drop, and the oxygen you provide to the baby will drop too. But precisely how much and whether it matters is unclear. I wish there was more I could say here. If it were me, I’d keep playing but probably pay a bit more attention to how I was feeling and take a break if I started to feel lightheaded.