When I had both of my births, I was attended by midwives. My first birth was attended by midwives, and my second birth was attended by professional midwives. My first birth, my son was actually almost born in the car because we didn't think my labor would progress very quickly. I only spent about 40 minutes in the water before my son was born. With my second son, I was in the water for about two and a half hours because I had a very fast labor. Most women will let the woman get into the water when they are six centimeters dilated. That's the amount of time I spent in the water. You can get in an out freely, if you want to. It really depends on the mom and what she wants to do.