EMBRYOLOGY AND FETAL DEVELOPMENT
Pregnancy is a sequence of events that normally includes fertilization,
implantation, embryonic growth, and fetal growth that terminates in birth (see
figure 2-1). Even though there are many events that take place in the reproductive
cycle, we cannot include every detail in this lesson. However, the following information
will give descriptive events of what goes on in the uterus prior to birth. This information
will also help you to recognize potential problems and to be able to intervene in the
nursing care process.
Figure 2-1. Growth of the fetus.
PRINCIPLES OF FERTILIZATION (CONCEPTION)
a. Fertilization refers to the joining together of the ovum (egg) and sperm cells.
The ovum originates in the graafian follicle within the ovary. The sperm cell originates
in the testes. The microscopic union of sperm and ovum increase in size more than 20
billion times from conception to birth. See figure 2-2 for union of sperm and ovum.