How does the baby breathe during a waterbirth?
There are several factors that prevent a baby from inhaling water at the time of birth. These inhibitory factors are normally present in all newborns. The baby in utero is oxygenated through the umbilical cord via the placenta, but practices for future air breathing by moving his intercostal muscles and diaphragm in a regular and rhythmic pattern from about 10 weeks gestation on. The lung fluids that are present are produced in the lungs and similar chemically to gastric fluids. These fluids come out into the mouth and are normally swallowed by the fetus. There is very little inspiration of amniotic fluid in utero. 24-48 hours before the onset of spontaneous labour the fetus experiences a notable increase in the Prostaglandin E2 levels from the placenta which cause a slowing down or stopping of the fetal breathing movements (FBM). With the work of the musculature of the diaphragm and intercostal muscles suspended, there is more blood flow to vital organs, including the brain. You can s
