1. Prenatal Development, Birth and The Newborn Behavioral Science Tues, Jan 26 2006

2. Prenatal Development Overview 3 Stages Major achievements of each stage Prenatal Developments Basic Concepts Critical periods Teratogens

3. 3 Stages of Prenatal Development Germinal Stage Embryonic Stage Fetal Stage

4. Germinal Stage Start – conception End – attachment to uterine wall Major achievements Rapid cell division Attachment to uterine wall

5. Embryo Stage 2 nd to 8 th week Start – attachment to uterine wall End – formation of bone cells Major achievements Growth (from ¼ inch to 1 inch) Major organs formed (~6.5 weeks) Movement

6. Critical Periods The developing child is most susceptible to teratogens during the embryonic stage This is when most of the major organ systems form and begin to function Each organ has a specific critical period And is influenced by different teratogens: E.g., Alcohol (FAS), Radiation, Tobacco, Maternal Disease

8. Fetal Stage 8 th week to ~38 weeks Start – formation of real bones End – birth Major achievements Growth (3 in. -> 20 in.) Movement felt by mother Hearing (~5months) Sensitive to light

9. Ovum The ovum is embedded in follicle cells

10. 17 th century drawing of Human sperm By Hartsoeker The miniature human was thought to grow once it entered the ovum

11. Sperm in the presence of an ovum

12. Ovum Sperm

13. The Germinal Stage

14. Overview of Germinal Stage

15. The Embryonic Stage

16. The start of the embyronic stage Implantation in uterine wall

17. Neural Tube (26 days) Head Heart Starts beating ~18 days 3 mm 0.12 in.

18. Chorion – develops into placenta

19. Heart Head ~ 3.5 weeks

20. Eye Mouth Nostrils Face at ~4.5 weeks

21. Eye Arm Leg 6 weeks

22. 5 – 6 Weeks 1.5 cm 0.6 in Primitive human form

23. Eye at 6 ½ weeks Eyes close ~ 9 weeks Open again at 7 months

24. 7 th week

25. The Fetal Stage

26. Formation of bone cells Beginning of the Fetal Stage

27. Fetal Movement

28. Fetal thumb sucking

29. 4 1/2 months 25 cm 10 in.

30. 5 ½ months 30 cm 12 in Layer of fat protects the skin (vernix)

31. Hand 5 weeks - bud 3 months - fingers 17 weeks – fingernails

32. Fetus and placenta

33. 5 months 25 cm 10 in.

34. 7 months Growth slows – If same growth rate continued the child would weigh ~200 lbs at birth 16 inches / 3 lbs Viable – able to survive outside the womb Age of viability now between 22-26 weeks Digestive / Respiratory systems working Babies born as little 1.5 lbs have been able to survive

35. Brain Development Occurs throughout prenatal period and after birth 3 major aspects Cell proliferation Development of new neurons Cell migration Neurons move to “proper” location Cell differentiation Neurons specialize

36. Birth Average Length = 20 inches Average weight = 7 lbs

37. Right after birth A few hours later

38. Effects of Alcohol Fetal Alcohol Syndrome High levels of prenatal exposure influence physical structure Lower levels of prenatal exposure influence neurochemistry Long lasting effects See Hunt et al., 1995

39. Low Birthweight

40. Cost of Low Birth Weight

43. The Newborn Assessment of Newborn Functioning Apgar Assessment Brazelton Neonatal Behavioral Assessment BNBAS Reflexes

44. APGAR Developed by Virginia Apgar (1950s) At birth – mother was the focus of attention Needed some sort of quick assessment of the infant Used right after birth Does not require much training

45. APGAR 5 Scales (all scored 0, 1, 2) Appearance Heart Rate Response to Stimulation Muscle Tone Respiration

46. APGAR Appearance (color of skin) 0 = gray / blue skin color Indicates lack of oxygen 1 = pink body / gray or blue hands Indicates lack of oxygen in extremities 2 = pink tone over entire body

47. APGAR Heart Rate 0 = no heart beat seen, heard, or felt 1 = less than 100 beats per minute 2 = 100 – 140 beats per minute Response to Stimulation Response to birth Response to suctioning of mouth / nose 0 = no response 1 = moderate of low response 2 = facial grimace / coughing / wheezing

48. APGAR Muscle Tone 0 = completely limp 1 = moderate muscle tone / limbs moderately flexed 2 = good muscle tone / limbs flexed & active Respiration 0 = no breathing within 60 seconds 1 = irregular or slow breathing 2 = good breathing / strong cry

49. APGAR Administered twice At 1 or 2 minutes and And again at 5 minutes Scores greater than 7 at 5 minutes indicate the infant is ok Likely no intervention is necessary Scores less than 4 indicate infant is in trouble Requires immediate attention

50. APGAR Scores on Apgar are strongly related to infant mortality Lower Apgar scores are related to a greater chance of the infant dying within the first year of life Mortality rates in US have dropped But rank far behind other countries 1997 - US Ranked # 27 in world Recent data suggests US has dropped farther

51. Infant Mortality Rates (Deaths per 1000 live births)

52. Brazelton Neonatal Behavioral Assessment Scale (BNBAS) Developed by T. Berry Brazelton, 1973 Designed to assess infant functioning over the first month of life Covers a wide range of behaviors Often used as a research tool Requires extensive training Requires ~45 minutes to administer entire asessment Should administer twice – use the higher score – greater validity

53. BNBAS Covers a broad range of behaviors Neurological items Based on the intensity of response Mainly focuses on reflexes 0 = Absent -> 3 = Appropriate response Behavioral items Focus on state of arousal (sleep to crying) 9 point scale used –  for most item midpoint is optimal

54. REFLEXES Automatic, stereotyped response to a specific stimuli Recent research suggest reflexes are variable Not completely the same every time Variability may be important for learning Enables the infant to “explore” the environment Learn about contingencies

55. Sucking Reflex Present Prenatally Stimuli - Touch face near lips Response – Sucking motion Becomes a skill (under voluntary control) by 3 months

56. Babinski Reflex Elicited by stroking the foot Response – Depends on age Infants – 0 to 3 months Toes fan out Older individuals Toes curl in

57. Moro Reflex Elicited by sudden drop Response Hands and legs go out to side and then return to middle Present at birth Drops out at about 6 months

58. Stepping Reflex Elicited by holding infant upright and moving them across a surface Response Rhythmic walking behavior Present at birth Drops out at ~ 4 months

59. Warning Signs of Neurological Problems Absent Reflex Weak or Delayed Reflex Unequal or Asymmetric Bilateral Reflex Reflex that re-emerges after it has dropped out Reflex that is supposed to drop out but doesn’t