Underwater
We have heard that giving birth while in a pool can actually be easier than in a hospital. Something about sitting in water and the baby being delivered into a pool of it apparently can be beneficial. We recommend you read up on it before you try it out, do not take our word for it.
One thing we are sure about though is that no one ever intended for a pregnant woman to submerge herself completely underwater like this. Good luck trying to give birth while you are a few feet underwater unless you can hold your breath for a few hours this could be very challenging, to say the least.