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.
An accidental fall is one way you can injure your abdomen (stomach) during pregnancy. You can do many things to prevent falls and accidents while you are pregnant: Wear comfortable shoes with flat or short heels, and avoid wearing high-heeled shoes. Use handrails when going up and down the stairs.