Which period of prenatal development is characterized as the longest?

The fetal period is the longest stage of prenatal development, lasting from about the ninth week after conception until birth. During this phase, the developing baby is known as a fetus, and it undergoes significant growth and maturation. This period is crucial as it involves the development of the organs and systems needed for survival outside the womb, as well as rapid physical growth.

In contrast, the germinal period occurs in the first two weeks post-conception and involves the formation of the zygote and initial cell division. The embryonic period follows, lasting from the second to the eighth week, and is characterized by the development of basic structures and the groundwork for organs, but it is a shorter timeframe. The pre-conception period, while important for planning and health aspects before pregnancy, is not considered part of prenatal development itself. Thus, the fetal period stands out as the longest stage, pivotal in preparing the fetus for life after birth.