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.
Traveling by Air During Pregnancy. Whether you are going by car, bus, or train, it is generally safe to travel while you are pregnant; however, there are some things to consider that could make your trip safer and more comfortable.1  It is essential to buckle-up every time you ride in a car.raveling by air is considered safe for women while they are pregnant; however, the following ideas might make your trip safer and more comfortable. 1  Most airlines allow pregnant women to travel through their eighth month.