The Fetal Period

• The fetal period extends from the beginning of the ninth week (third month) until the birth
• During this period, there is tremendous growth and specialization of the body structures.
• It is characterized by the maturation of tissues and organs and the rapid growth of the body.
• Growth in length is particularly striking during the third, fourth, and fifth months, while an increase in weight is most striking during the last 2 months of gestation.

The prenatal period ends with parturition and is followed by a long postnatal period. Only at about age 25 years are the last progressive changes completed.