Conception is the union of ovum and spermatozoon. It is the start of a new life.Within this simple book, there is an overview on how pregnancy develop, moreover how the baby can survive and how the development process occurs. - The term embryo is used during the first 8 weeks of development. It is important to know the events that occur in the beginnings of life, when all the blueprints of the human body are laid down in the embryo. The embryonic period is followed by the fetal period (months 3-9) when there is extensive growth and differentiation and when the embryo acquires a more human form