一、年龄分期:凡14岁以下称儿童(15至17岁称少年,18至25岁称青年),儿童共分六个阶段. 从受孕至分娩约40周为胎儿期;出生后一个月内为新生儿期;出生后1—12个月为婴儿期;1—3岁为幼儿期;4—6岁为学龄前期;7—14岁为学龄期。二、头颅发育:新生儿头颅长度占身长的1/4(成人仅占1/8),颅骨前囟(俗称 First, the age of staging: all children under the age of 14 (15 to 17 years of age, 18 to 25 years of age, said young children), the child is divided into six stages.From pregnancy to birth about 40 weeks for the fetus; within one month after birth For the neonatal period; 1-12 months after birth as a baby; 1-3 years as a child care; 4-6 years of preschool; 7-14 years of age. Second, head development: the length of the head of neonatal head length of 1/4 (adults only 1/8), the skull anterior fontanelle