The prenatal period of development is very important to the health and cognitive development of the unborn baby. This is a time when a mother should stay healthy and stay away from drugs, alcohol and tobacco. She should take additional health precaution such as adding prenatal vitamins to her diet. During the prenatal period, the baby is forming physically and cognitively. Organs, brain functions and body parts are all form from a single cell. Everything that happens during this period affects the baby acutely.