1. Prenatal and Infant Growth ©Gallahue, D.L., Ozmun, J.C., Goodway, J.D. (2012). Understanding Motor Development. Boston: McGraw-Hill. McGraw-Hill/Irwin © 2012 McGraw-Hill Companies. All Rights Reserved.

2. 6-2 The rate of growth from conception through infancy is unsurpassed throughout the rest of life.

3. 6-3  Zygotic Period : Conception – 1 st week  Diameter = 2.5mm.(0.01in.)  50% spontaneously abort  Embryonic Period : 2 nd week – 2 nd month  Ectoderm/mesoderm/endoderm (table 6.1)  Differentiation (figure 6.1)  At-risk for congenital malformations

4. 6-4  Early Fetal Period: 3 rd – 6 th month  Rapid growth period  4 th month most rapid  Doubles wt. (4oz/113g) & length (6-8in/15- 20cm)  Lanugo : Fine hair covering  Vernix Caseosa : Fatty jell protection  Structurally complete; functionally immature by end of 6 th month; age of viability

5. 6-5  Later Fetal Period: 7 th -9 th month  Weight triples (table 6.2)  Lanugo & Vernix fluid disappear  7 th month is a quiet period  8 th -9 th months more activity  Normal gestation: 38-42 weeks  Typical full term newborn  length: 19-21 in (48-53 cm)  weight: 6-8lbs (3-4kg)

6. 6-6  Neonatal Period : Birth-4 weeks  Body proportions (figure 6.2)  Body weight: Males 4%> females  Potential for catch-up growth among LBW, VLBW & ELBW infants (see: Developmental Dilemma )  Early Infancy: 4 weeks-1 year  Rapid gains in height & weight  Weight triples by end of 1 st year  Length increases to about 30 in (76cm) by 1 st birthday

7. 6-7  Later Infancy: 12 months – 24 months  Growth: Rapid but slower than 1 st year  Dimensions at 2 nd birthday:  Girls: Length= 34in (86cm); weight = 26lbs (12kg)  Boys: Length = 35in (89cm); weight = 28lbs (12.7kg)  Correlation:.60 between height & weight  an uneven process of developmental direction process  WHO vs. CDC Growth charts: ( see: International Perspectives )  Girls: (figures 6.3)  Boys: (figure 6.4)

8. 6-8 Growth during infancy is a rapid but uneven process influenced by the principles of proximodistal and cephalocaudal development.