Pregnancy is considered by many as not less than a miracle. It is divided into three parts or trimesters. The first three months consist of the first trimester, the fourth month through the sixth month is the second trimester and from the seventh month till the delivery or the ninth month is the third trimester. During prenatal development, all three trimesters are very important and any kind of psychological or medical condition the mother undergoes, the child is equally affected. Therefore, the would-be mother needs to be careful in terms of food, medications, nutrition, exercise, and all aspects of life.
Since the first trimester is the riskiest and a period vital for all developmental activities, it is comparatively considered to be the most important one. It is the stage during which spontaneous abortions can occur. Besides, this is the time when all the developmental activities begin and each organ starts to develop. The second and the third trimesters are only the further development of the organs and the body fat. In the first trimester, the initial and the most important stage in the development of three layers is the ectoderm, mesoderm, and endoderm. These are the three basic layers from the sense organs, nervous, circulatory, skeletal, muscular, digestive and the endocrine systems develops without which we will not be complete human being. By the end of the third month of the first trimester, most of the organs such as the liver, kidney, heart, brain, and all other vital organs are formed and also begin to function. Once the first trimester is passed, it is considered that the riskiest stage is passed. However, it is important to note that during the third trimester, if the baby is born prematurely, it could survive with extra support but if birth occurs before the third trimester, the survival is difficult even with extraordinary medical care in a neonatal intensive care unit.
Reference
Child Development Institute. Approximate Timetable of Prenatal Development. (2007). Web.