Prenatal Development, Birth, and the Newborn Chapter 3: Prenatal Development, Birth, and the Newborn

Chapter 3: Prenatal Development, Birth, and the Newborn Chapter 3 has four modules: Module 3.1 From Conception to Birth Module 3.2 Influences on Prenatal Development Module 3.3 Happy Birthday! Module 3.4 The Newborn

From Conception to Birth Period of the Zygote (Weeks 1-2) Period of the Embryo (Weeks 3-8) Period of the Fetus (Weeks 9-38)

Module 3.1 From Conception to Birth What happens to a fertilized egg in the first 2 weeks after conception? When do body structures and internal organs emerge in prenatal development? When do body systems begin to function well enough to support life? Module 3.2 Influences on Prenatal Development Module 3.3 Happy Birthday! Module 3.4 The Newborn

Let’s look at the next slide to view this period more closely. Period of the Zygote Key terms: Ovulation; fertilization, implantation, fallopian tube; zygote, blastocyst; germ disc Characteristics: 2 weeks duration; rapid division Let’s look at the next slide to view this period more closely. Begins when egg is fertilized in the fallopian tube After about 4 days, the zygote consists of about 100 cells, resembles a hollowball,and is called a blastocyst Period of rapid cell division Ends 2 weeks later when the zygote is implanted in the wall of the uterus Germ disc: A small cluster of cells near the center of the blastocyst, eventually develops into the baby

Period of the Zygote

Period of the Embryo Key terms: Embryo Ectoderm, mesoderm, endoderm Amnion and amniotic fluid Umbilical cord Placenta Villi Characteristics: Third to eighth weeks of prenatal development Differentiation of organs and organ systems occurs After the blastocyst is completely embedded in the uterine wall, it is called an embryo From 3 to 8 weeks after conception Three layers form the embryo: ectoderm, mesoderm, endoderm Body parts are formed during this period Embryo rests in the amnion filled with amniotic fluid Umbilical cord joins embryo to placenta Villi: finger-like projections from the umbilical blood vessels

Prenatal Structures

Period of the Fetus Key Terms: Cerebral cortex Vernix Age of viability Characteristics: From 9 weeks after conception to birth Increase in size Systems begin to function From 9 weeks after conception to birth Increase in size and systems begin to function Cerebral cortex: the wrinkled surface of the brain that regulates many important human behaviors Vernix: protects the fetus during its long bath in amniotic fluid Age of viability: occurs at between 22 and 28 weeks; fetus has a chance to survive

Period of the Fetus Fetal Behavior: Fetal movement Behavioral maturity of sense Changes during prenatal development See Summary Table on page 71

Five Steps Toward a Healthy Baby Regular check-ups Healthy foods No alcohol or caffeinated beverages Exercise Adequate diet

Influences on Prenatal Development General Risk Factors Teratogens: Diseases, Drugs, and Environmental Hazards How Teratogens Influence Prenatal Development Prenatal Diagnosis and Treatment

Module 3.2 Influences on Prenatal Development Module 3.1 From Conception to Birth Module 3.2 Influences on Prenatal Development How is prenatal development influenced by a pregnant woman’s nutrition, the stress she experiences while pregnant, and her age? What is a teratogen, and what specific diseases, drugs, and environmental hazards can be teratogens? How do teratogens affect prenatal development? How can prenatal development be monitored? Can abnormal prenatal development be corrected? Module 3.3 Happy Birthday! Module 3.4 The Newborn

General Risk Factors Nutrition Chronic stress Mother’s age Nutrition: adequate amount of food, protein, vitamins, & minerals (ex. spina bifida caused by inadequate levels of folic acid) Stress: decreases oxygen to fetus, weakens mother’s immune system, and leads to unhealthy behaviors such as smoking or drinking alcohol Mother’s Age: neither too young nor too old is best

Teratogens: Diseases, Drugs, and Environmental Hazards Teratogen: agent that causes abnormal prenatal development Diseases passing through placenta directly or attacking at birth (Table 3-1) Potentially dangerous drugs (Table 3-2) Environmental hazards (Table 3-3) Many diseases pass through the placenta directly and attack the fetus; others attack at birth Potentially dangerous drugs are not limited to cocaine but include alcohol, caffeine, and aspirin (ex. fetal alcohol syndrome) Environmental hazards are treacherous because we’re often unaware of their presence

Did you hear that? Is cell phone usage a potential teratogen for pregnant women? Yes

How Teratogens Influence Prenatal Development Impact of teratogen depends on organism genotype Impact of teratogens changes over course of prenatal development and depends on dose Each teratogen affects a specific aspect (or aspects) of prenatal development Damage is not always evident at birth See pages 80-82

Let’s review the effects of teratogens across prenatal development.

Prenatal Diagnosis and Treatment Ultrasound Amniocentesis Chorionic villus sampling (CVS) These can detect physical deformities and genetic disorders

Prenatal Diagnosis Chorionic Villus Sampling Amniocentesis Amniocentesis: sample taken of amniotic fluid surrounding fetus (through mother’s abdomen) CVS: sample of tissue obtained from chorion Amniocentesis Chorionic Villus Sampling

Prenatal Diagnosis and Treatment Fetal medicine Fetal surgery

Happy Birthday! Labor and Delivery Approaches to Childbirth Adjusting to Parenthood Birth Complications

What are the stages in labor and delivery? Module 3.1 From Conception to Birth Module 3.2 Influences on Prenatal Development Module 3.3 Happy Birthday! What are the stages in labor and delivery? What are “natural” ways of coping with the pain of childbirth? Is childbirth at home safe? What are the effects of postpartum depression? What are some complications that can occur during birth? Module 3.4 The Newborn

Labor and Delivery Labor is usually divided into three stages Starts when muscles of uterus contract and ends when cervix is fully enlarged Stage 2 Baby is pushed through the birth canal Stage 3 Placenta is expelled Labor is usually divided into three stages Labor is usually divided into three stages Stage 1: starts when the muscles of the uterus contract and ends when the cervix is fully enlarged (about 10 cm) Stage 2: baby is pushed through the birth canal Crowning Breech presentation Stage 3: placenta is expelled (afterbirth)

Three Stages of Labor See Summary Table on Page 88

Approaches to Childbirth Prepared childbirth Natural childbirth Childbirth with doula Choice of place of birth

Approaches to Childbirth Childbirth classes Content Benefits Childbirth classes provide information about pregnancy and childbirth Childbirth classes teach pain control through deep breathing, imagery, and supportive coaching (doula) Mothers who attend classes use less medication during labor and feel more positive about labor and birth

Adjusting to Parenthood Reorganization of old routines Physical and emotional reactions Postpartum depression Parents often reorganize old routines Half of all new moms feel some irritation, resentment, and experience crying 10-15% feel more severe postpartum depression Postpartum depression affects warmth and enthusiasm of mothering

Birth Complications Hypoxia Cephalopelvic disproportion Irregular position Preeclampsia Prolapsed umbilical cord Lack of oxygen (hypoxia): often leads to surgical removal of the fetus (C-section)

Birth Complications Prematurity Low birth weight Premature and small-for-date infants Prematurity is less serious than being small- for-date

True or False? Infant mortality is relatively low in the United States compared to other industrialized countries. Let’s look at these rates around the world. False. Infant mortality is relatively high in the United States compared to other industrialized countries.

Infant Mortality Rates Look at the infant mortality rates above Ask: Do you know what contributes to these statistics?

The Newborn Assessing the Newborn The Newborn’s Reflexes Newborn States Perception and Learning in the Newborn

How do reflexes help newborns interact with the world? Module 3.1 From Conception to Birth Module 3.2 Influences on Prenatal Development Module 3.3 Happy Birthday! Module 3.4 The Newborn How do we determine if a baby is healthy and adjusting to life outside the uterus? How do reflexes help newborns interact with the world? What behavioral states are observable in newborns? How well do newborns experience the world? Can they learn from experience?

Assessing the Newborn Apgar score (Table 3-5) Neonatal Behavioral Assessment Scale (NBAS) The Apgar assesses newborns’ health including activity, pulse, grimace, appearance, and respiration The Neonatal Behavioral Assessment Scale (NBAS) is a comprehensive assessment of infants that includes measures of alertness and ability to interact with people

The Newborn’s Reflexes Newborns’ reflexes prepare them to interact with the world Survival reflexes Protective reflexes Foundational reflexes Newborns’ reflexes prepare them to interact with the world Some reflexes are important to survival (e.g., rooting and sucking) Some protect the newborn (e.g., blink and withdrawal) Some are foundations for later motor behavior

Newborn States: Primary Four primary states Alert inactivity Waking activity Crying Sleeping

Newborn States: Cries Three distinctive types of cries Basic Mad Pain Swaddling is a useful technique to help soothe babies

Newborn States: Sleep Developmental change in sleep-wake cycle Types of sleep (REM/non-REM) Co-sleeping

Back to Sleep Campaign The Back to Sleep campaign began in 1994 as a way to educate parents, caregivers, and health care providers about ways to reduce the risk for Sudden Infant Death Syndrome (SIDS). The campaign was named for its recommendation to place healthy babies on their backs to sleep. Placing babies on their backs to sleep reduces the risk for SIDS, also known as "crib death." This campaign has been successful in promoting infant back sleeping and other risk-reduction strategies to parents, family members, child care providers, health professionals, and all other caregivers of infants.

Perception and Learning in the Newborn All the basic perceptual processes are operating at birth Newborns can see, hear, taste, smell, and feel Newborns can also learn and remember