1. Kathleen Stassen Berger The Developing Person Through Childhood and Adolescence Ninth Edition Part I Prenatal Development and Birth Chapter Four

2. CHAPTER PREVIEW Anticipating the birth of a child is one of life’s most enriching experiences. The period of prenatal development is a time of incredibly rapid growth. The emerging person develops from a single cell into a fully functioning individual. This development is outlined in Chapter 4, followed by a discussion of the birth process.

3. CHAPTER PREVIEW (CONT.) The fetus becomes a separate human being who begins life almost completely dependent upon its caregivers. Problems that can occur—among them prenatal exposure to disease, drugs, and other hazards—and the factors that moderate the risks of teratogenic exposure. One sign. problem is low birthweight, which is generally linked to maternal malnutrition and drug use. Concludes with a discussion of the significance of the parent–newborn bond.

4. Figure 4.1 The Most Dangerous Journey Berger: The Developing Person Through Childhood and Adolescence, Ninth Edition Copyright © 2012 by Worth Publishers

5. Table 4.1 Timing and Terminology Berger: The Developing Person Through Childhood and Adolescence, Ninth Edition Copyright © 2012 by Worth Publishers

6. Prenatal Growth Germinal: The First 14 days Embryo: From the Third Through the Eighth Week Fetus: From the Ninth Week Until Birth

7. Germinal Period (First 14 days) The germinal period is the first two weeks of prenatal development after conception, characterized by rapid cell division and the beginning of cell differentiation. About a week after conception, the multiplying cells (now numbering more than 100) separate into two distinct masses. The outer cells form a shell that will become the placenta (the organ that surrounds and protects the developing creature), and the inner cells form a nucleus that will become the embryo.

8. Germinal Period (Cont.) The first task of the outer cells is to achieve implantation— that is, to embed themselves in the nurturing lining of the uterus. This is far from automatic; about 50 percent of natural conceptions and 70 percent of in vitro conceptions do not implant. Thus, most new life ends before an embryo begins.

9. Embryonic (3rd - 8th Weeks) Formless Mass becomes a distinct being known as the embryo. A thin line down the middle of the embryo (the primitive streak) forms a structure that becomes the neural tube, then the brain and spinal column (the central nervous system). In the fourth week, the cardiovascular system is functioning; the eyes, ears, nose, and mouth start to form. At five weeks, the arm and leg buds appear.

10. Embryonic (3 rd to 8 th Weeks) By the end of the second month, the developing organism weighs about 1 gram (1/30 ounce), is 21/2 centimeters (1 inch) long, and has all the basic organs and body parts of a human being (except the sex organs).

11. Brain Facial Features External sex organs Intestines Arms, hands and fingers As nerves and muscles form links to the brain, the embryo now moves spontaneously, as the brain begins to move muscles. Eyes and eyelids are developed. Eyes will continue to migrate to the front of the head, where they will eventually rest. Eyelids begin to grow together and are only half closed. External, middle, and inner ears are now fully formed. External ears will continue to migrate to the side of the head, where they will eventually rest. Urogenital membranes have developed into either male or female organs, and ovaries or testicles are visible. Clitoris or penis begins to form, but distinguishing the embryo’s sex is difficult. The intestines begin to move from the umbilical cord to the embryo’s body cavity. Arms are well formed, longer, and can bend at elbows and move forward. Fingers elongate and digits are fully separated. Each finger has three digits, and the thumb has two digits. Overall appearance The head is still disproportionately large but is erect and appears rounded. The neck is well defined. The tail will disappear by the end of this week. Cartilage begins to turn into bone. The ectoderm layer is replaced by the beginnings of skin. The body becomes evenly rounded, due to the growth in the abdomen. Brain Facial Features External sex organs Overall appearance Arms, hands and fingers Intestines 11 What happens during the embryonic period of prenatal development? From the Third Through the Eighth Week

12. Embryonic What body parts develop during the embryonic period? The brain and spinal column, eyes, ears, nose, and mouth start to form as do the heart, arms and legs. This is followed by the upper arm, forearm, palms, webbed fingers, legs, knees, feet and webbed toes.

13. Prenatal Development Prenatal development is cephalocaudal, meaning that it proceeds from “head to tail,” and proximodistal, or from “near to far."

14. Fetal Period (9 th Week until Birth) In the fourth, fifth, and sixth months, the heartbeat becomes stronger. Digestive and excretory systems develop. Fingernails, toenails, and buds for teeth form, and hair grows (including eyelashes). The brain increases about six times in size and develops many new neurons (neurogenesis) and synapses (synaptogenesis). Up to half a million brain cells per minute are created at peak growth during mid-pregnancy (Dowling, 2004).

15. During the fetal period, if the fetus is male (XY), the SRY gene on the Y chromosome signals the development of male sex organs. If the fetus is female (XX), no signal is sent, and the fetus begins to develop female sex organs. Most functions of the brain are gender-neutral; some neurological sex differences occur in the third month. Fetal Period

16. At the end of the third month, the fetus has all its body parts, weighs approximately 3 ounces (87 grams), and is about 3 inches (7.5 centimeters) long. In the middle 3 months, the systems develop more fully. The crucial factor in the fetus’s attaining the age of viability, beginning at about 22 weeks, is brain maturation, which is essential to the regulation of basic body functions, such as breathing and sucking.

17. Last Three Months In the last three months of prenatal life, the lungs begin to expand and contract, exercising muscles involved in breathing by using the amniotic fluid as a substitute for air. The valves of the heart go through a final maturation, as do the arteries and veins throughout the body. Among other things, this helps to prevent “brain bleeds,” one of the hazards of preterm birth in which paper thin blood vessels in the skull collapse.

18. Table 4.2 Vulnerability During Prenatal Development Berger: The Developing Person Through Childhood and Adolescence, Ninth Edition Copyright © 2012 by Worth Publishers

19. What are some prenatal tests? 19 Benefits of Prenatal Care

20. Figure 4.3 Prenatal Growth of the Brain Berger: The Developing Person Through Childhood and Adolescence, Ninth Edition Copyright © 2012 by Worth Publishers

21. fetus: A developing human organism from the start of the ninth week after conception until birth. 21 What happens during the fetal period of prenatal development? 91212 1616 2020 2424 2828 3232 3636 3838 From the Ninth Week until Birth 9 weeks through 38 weeks

22. Birth Birth usually begins at about 38 weeks after conception, when the fetus’s brain signals the release of hormones, specifically oxytocin, that trigger uterine contractions in the mother. The baby is born, on average, after 12 hours of active labor for first births and 7 hours for subsequent births.

23. Figure 4.4 A Normal, Uncomplicated Birth Berger: The Developing Person Through Childhood and Adolescence, Ninth Edition Copyright © 2012 by Worth Publishers

24. Birth The quality of the birth experience depends on many factors, including the parents’ preparation for birth, the skill of the birth attendants, the position and size of the fetus, and the customs of the culture. Cesarean sections (c-sections) account for more than one-third of U.S. births. Less studied is the epidural, a spinal injection to ease pain. Another medical intervention is induced labor.

25. Birth Most U.S. births occur in hospital labor rooms. Another 5 percent occur in birthing centers. Only 1 percent of U.S. births take place at home. They are usually normal and healthy but risk complications. Many North American mothers today use a professional birth coach, or doula, to assist them.

26. Apgar Scale Used to assign a score between 0 and 2 to the newborn’s heart rate, breathing, muscle tone, color, and reflexes at one minute after birth and again at five minutes. A score of 7 or better indicates the newborn is not in danger; below 7, that the infant needs help in establishing normal breathing; and below 4, that the baby is in critical condition and needs immediate medical attention.

27. Table 4.3 Criteria and Scoring of the Apgar Scale Berger: The Developing Person Through Childhood and Adolescence, Ninth Edition Copyright © 2012 by Worth Publishers

28. Preterm and a Robust Newborn What are three major reasons why pregnancy continues months after the fetus could live outside the uterus? The critical difference between life and death, or between a fragile preterm baby and a robust newborn, is maturation of the neurological, respiratory, and cardiovascular systems.

29. Teratogens Include such substances or conditions as viruses, drugs, chemicals, stressors, and pollutants that can impair prenatal development and lead to birth defects, even death. Teratogens that tend to harm the prenatal brain are called behavioral teratogens. Approximately 20 percent of all children have behavioral difficulties that could be related to behavioral teratogens.

30. Teratology Teratology is a science of risk analysis, which attempts to evaluate what factors can make prenatal harm more, or less, likely to occur.

31. Teratogen Three crucial factors that determine whether a specific teratogen will cause harm, and of what nature, are the timing of exposure, the amount of exposure, and the developing organism’s genetic vulnerability to damage from the substance.

32. Teratogen Although each body structure has its own critical period during which it is most susceptible to teratogenic damage, health during the entire fetal period affects the brain. Some teratogens have a cumulative effect on the developing individual. For other teratogens, there is a threshold effect; that is, the substance is virtually harmless until exposure reaches a certain level.

33. Table 4.4 Teratogens: Effects of Exposure and Prevention of Damage Berger: The Developing Person Through Childhood and Adolescence, Ninth Edition Copyright © 2012 by Worth Publishers

35. Fetal Alcohol Syndrome Early in pregnancy, large doses of alcohol can trigger the physical, behavioral, and mental symptoms of fetal alcohol syndrome (FAS). Later in pregnancy, alcohol is a behavioral teratogen, the cause of fetal alcohol effects (FAE).

36. Problems A deficiency in folic acid in the mother’s diet may result in neural-tube defects, such as spina bifida or anencephaly. These also occur more commonly in certain ethnic groups. Early prenatal care protects fetal growth, makes birth easier, and makes parents better able to cope with birth. Laboratory test results sometimes produce false positives because they incorrectly suggest a problem that does not exist.

37. Low Birthweight Low birthweight (LBW) is defined as birthweight that is less than 51/2 pounds (2,500 grams). Babies who weigh less than 3 pounds, 5 ounces (1,500 grams) are classified as very low birthweight (VLBW); those who weigh less than 2 pounds, 3 ounces (1,000 grams) are classified as extremely low birthweight (ELBW). Low-birthweight infants who are born 3 or more weeks early are called preterm. Others, born close to the due date but weighing less than most full-term newborns, are called small for gestational age (SGA).

38. Culture Influence Not only are fathers important to the birth process, but the entire social network and culture are crucial influences. This is most apparent in what has been called the Hispanic paradox, which says that although immigrants to the U.S. are poorer and have less adequate prenatal care, they have healthier newborns than American-born mothers of the same ethnic background.

39. LBW Worldwide, the LBW rate is lower than it was 20 years ago. The U.S. infant mortality rate of about 7 per 1,000 is primarily because of low birth weight. In US, African Americans have LBW newborns twice as often as the national avg. The birth rate has < in the past 20 yrs. Nations with many small newborns are also nations where hunger is high.

40. Figure 4.2 Each Critical Day Berger: The Developing Person Through Childhood and Adolescence, Ninth Edition Copyright © 2012 by Worth Publishers

41. Birth Complications More likely if the fetus is already at risk because of low weight, preterm birth, genetic abnormality, or teratogenic exposure or because the mother is unusually young, old, small, or ill.

42. Cerebral Palsy (CP) Researchers now realize that cerebral palsy (difficulties with movement control resulting from brain damage) results from genetic vulnerability, worsened by teratogens, maternal infection, and a birth in which anoxia (a temporary lack of oxygen) occurs.

43. NEWBORN Newborns are social beings that respond to others in many ways. The test that measures behavioral responsiveness in newborns is the Brazelton Neonatal Assessment Scale (NBAS). The test measures 46 behaviors, 20 of which are reflexes.

44. REFLEXES The breathing reflex is an involuntary response that causes the newborn to take the first breath even before the umbilical cord is cut. Other reflexive behaviors that maintain oxygen are hiccups, sneezes, and thrashing.

45. REFLEXES Shivering, crying, and tucking the legs close to the body are examples of reflexes that help to maintain constant body temperature.

46. REFLEXES A third set of reflexes relates to feeding - suck anything that touches the lips; to turn their heads and start to suck when something brushes against their cheek-rooting reflex. Other important reflexes that facilitate this behavior are swallowing, crying, and spitting up.

47. FATHER The presence of the father reduces complications during birth - helps the mother. Many fathers experience symptoms of preg.- weight gain, indigestion, and pain during labor. Crucial re the birth experience is the formation of a strong parental alliance between the parents.

48. Postpartum Depression Some mothers may develop feelings of sadness and inadequacy, or postpartum depression, in the days and weeks after birth. What are the signs of postpartum depression? One sign is feelings of euphoria after birth that give way to sleeplessness and feelings of sadness and inadequacy. Caring for the infant becomes a burden or seems overwhelming.

49. Parent-Infant Bond The term parent–infant bond is used to emphasize the strong, loving connection that forms between parent and child in the early moments after birth. For vulnerable infants, parents are encouraged to help with early caregiving in the hospital. This reduces stress in both infant and parents. One ex. of early caregiving is kangaroo care - mothers of low- birthweight infants spend extra time holding their infants between their breasts.

50. Kangaroo Care What are the results of kangaroo care? A rise in infant adjustment to life outside of the womb as well as increased parental sensitivity and effectiveness are results of kangaroo care. Results are seen in weight gain, more time in deep stages of sleep and more alert awake time spent by infants receiving kangaroo care.