Carbon dioxide. Carbon dioxide (chemical formula CO2) is a colorless gas with a density about 60% higher than that of air (1.225 g/L) that is odorless at normally encountered concentrations. Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms.
You should only do ballet in pregnancy if you are used to it. Ballet stretches can place a lot of pressure on your joints, especially your pelvic joints, and standing on one leg can cause pain in your pelvis.
During pregnancy you may find yourself wrestling in bed trying to get comfortable before falling asleep. Unfortunately, your regular sleeping positions may no longer work for you during pregnancy. There are a number of reasons for this new discomfort, but there are some sleeping positions that you can try that may help you get your much needed rest.