Chapter 3: Prenatal Development, Birth, and the Newborn Baby
T. Berry Brazelton's Neonatal Behavioral Assessment Scale (NBAS)
Evaluates the new born's reflexes, muscle tone, state changes, responsiveness to physical and social stimuli, and other reactions --Changes in scores over the first week or two of life provide the best estimate of the baby's ability to recover from the stress of birth --NBAS recovery curves predict intelligence and absence of emotional and behavior problems w/ moderate success well into the preschool years
Age of Viability
--The point at which the baby can first survive occurs sometime between 22 and 26 weeks
First Semester: Embryo (3-4, 5-8 weeks) - Chart
--A primitive brain and spinal cord appear, heart, muscles, ribs, backbone, and digestive tract begin to develop --Many external body structures (Face, arms, legs, toes, fingers) and internal organs form, and production and migration of neurons in the brain begin, the sense of touch starts to develop, and the embryo can move
Preterm Infants
--Are born several weeks or more before their due date --Weight could still possibly by appropriate --Showed slightly lower reading and math scores --Cared for in a special Plexiglas-enclosed bed called an isolate (temp=carefully controlled)
Hearing
--At birth, infants prefer complex sounds to pure tones --Can detect the sounds of any human language
Illegal Drugs
--Babies born to users of cocaine, heroin, or methadone are at risk for a wide variety of problems, including prematurity, low birth weight, brain abnormalities, physical defects, breathing difficulties, etc --Herion/methadone babies: infants are less attentive to the environment, motor development is slow
Small-for-date Infants
--Below their expected weight considering the length of the pregnancy --Some are full-term --Usually have more serious problems than preterm infants --more likely to catch infections, have brain damage, and die --Smaller and lower intelligence levels in middle childhood --May be caused to poor nutrition before birth, or babies themselves had defects --LIKELY to suffer from neurological impairment that permanently weakens their capacity to manage stress
Taste and Smell
--Can distinguish several basic tastes --Young infants will learn to prefer a test that at first evoked a negative response --Sense of smell helps moms and babies identify each other --Babies prefer odor of their own's mother's breasts after 2-4 days than another woman's
Germinal: Placenta and Umbilical Cord
--Cells of the trophoblast form another protective membrane- the chorion, which surrounds the amnion --From the chorion, tiny fingerlike villi, or blood vessels, emerge --Placenta: permits food and oxygen to reach the developing organism and waste products to be carried away
Maternal Factors: Nutrition
--Depend on mothers for nutrients --Malnutrition can cause damage to central nervous system and immune system --Prenatally malnourished babes usually catch respiratory illnesses --Folic acid supplementation in early pregnancy can lessen physical defects
The harm done by teratogens depends on:
--Dose: larger doses over longer time periods usually have more negative effects --Heredity: Genetic makeup of the mother and the developing organism plays an important role --Other negative influences: The presence of several negative factors at once, such as additional teratogens/poor nutrition --Age: The effects of teratogens vary w/ the age of the organism at time of exposure
Tobacco Babies
--Even when a baby of smoking mother appears to be born in good physical condition, slight behavioral abnormalities may threaten development
3) Delivery of the placenta
--Final few pushes --Cause placenta to separate from the wall of the uterus and be delivered in about 5-10 mins
Impact of teratogens at certain times
--Germinal: rarely have any impact, if they do, the tiny mass of cells is usually so damaged they die --Embryonic: serious defects are most likely to occur b/c the foundations for all body parts are being laid down --Fetal Period: Teratogenic damage = usually minor, organs like brain, ears, eyes, etc can be strongly impacted
Viruses
--HIV, which can lead to AIDS, a disease that destroys the immune system, had infected increasing #s of women --AIDS progresses fast in infants, weight loss, diarrhea, brain damage indicated by seizures
Anoxia
--Inadequate oxygen supply --One of the causes of cerebral palsy
First Semester: The Germinal Period - Chart
--Lasts about 2 weeks --The one-celled zygote multiplies and forms a blastocyst --Blastocyst burrows into the uterine lining, structures that feed and protect the developing organism begin to form--amnion, chorion, yolk sac, placenta, and umbilical cord
2) Delivery of the baby
--Lasts about 50 mins for first birth/20 mins for later births --Mom feels natural urge to squeeze and push --Near the end of this stage, the shoulders emerge, followed quickly by the rest of the baby's body
Vision
--Least developed sense at birth --Can't focus their eyes well --Visual acuity (fineness of discrimination) is limited --Takes about 4 months for color vision to become adultlike
1) Dilation and effacement of the cervix
--Longest stage (12-14 hours w/ first birth & 4-6 for later births) --Contractions of uterus become more frequent/powerful --Causes cervix to widen and thin to nothing, forming a clear channel from the uterus to the vagina --Transition reached when frequency/strength at peak, cervix completely open
Oxytocin
--Mother's produce higher levels of the hormone toward the end of pregnancy --Stimulates uterine contractions, causes the breasts to let down milk, induces calm mood, promotes responsiveness to baby
Maternal Factors
--Nutrition --Emotional Stress --Rh Factor Incompatibility --Maternal Age
Maternal Factors: Emotional Stress
--When moms experience severe stress: babies at risk for lot --Higher risk of miscarriage, prematurity, low birth weight, infant respiratory, and digestive illnesses --Can cause rise in fetal stress hormones and therefore, heart rate, BP, blood glucose of fetus --Associated w/ negative behavioral outcomes such as anxiety, short attention, aggression
Touch
--promotes growth --newborns can distinguish shape and texture --highly sensitive to pain --Breast milk calms babies down
Last Half of the First Month
1) the ectoderm, which will become the nervous system and skin; 2) the mesoderm, from which will develop the muscles, skeleton, circulatory system, and other internal organs 3) the endoderm, which will become the digestive system, lungs, urinary tract, and glands
Sperm can live up to ______ days once in the fallopian tubes
6
Doula
A Greek word referring to a trained lay attendant-- who stayed with them throughout labor and delivery, talking to them, holding their hands, and rubbing their backs to promote relaxation
Reflex
An inborn, automatic response to a particular form of stimulation
Fetal Monitors
Electronic instruments that track the baby's heart rate during labor --Abnormal heartbeat pattern may indicate that the baby is in distress due to anoxia and needs to be delivered immediately
Germinal Period: Implantation
Between the 7th and 9th days, implantation occurs --The blastocyst burrows deep into the uterine lining --The trophoblast multiplies fastest and forms a membrane, called the amnion, that encloses the developing organism in amniotic fluid, which helps keep the temp of the prenatal world constant and provides a cushion against jolts caused by the woman's movement --A yolk sac emerges that produces blood cells until the developing liver, spleen, and bone marrow are mature enough to take over this function
Preclampsia
Blood pressure increases sharply and the face, hands, and feet swell in the last half of pregnancy --Can cause convulsions in the mother and fetal death if untreated --Usually, hospitalization, bed rest, and drugs can lower BP to normal level, otherwise, the baby must be delivered at once
Rapid-Eye-Movement (REM) Sleep
Brain-wave activity is remarkable similar to that of the waking state --Eyes dart beneath the lids; heart rate, BP, and breathing uneven, slight body movements
Five states of arousal
Degrees of sleep and wakefulness 1) Regular, or NREM, sleep: infant at full rest, little/no body activity, no movements, eyes closed (8-9 hours) 2) Irregular, or REM, sleep: Gentle limb movements, facial grimacing, rapid eye movements underneath eyelids, breathing irregular (8-9 hours) 3) Drowsiness: Infant either falling asleep or waking up, body less active than in irregular sleep, eyes open and close, breathing even but faster than regular sleep (varies) 4) Quiet Alertness: Body is relatively inactive, with eyes open and attentive, breathing even (2-3 hours) 5) Waking activity/crying: Frequent bursts of uncoordinated body activity, breathing v irregular, face may be relaxed or tense, crying may occur (1-4 hours)
Vernix
Emerges on the skin, protecting it from chapping during the long months spent bathing in the amniotic fluid
Non-Rapid-Eye-Movement (NREM) Sleep
The body is almost motionless, and heart rate, breathing, and brain-wave activity are slow/even
Fallopian Tubes
Long, thin structures that lead to the hollow, softly lined uterus
Trimesters
Three equal time periods
In a typical natural childbirth program, the expectant mother participates in these three activities:
1) Classes: Learn about anatomy and physiology of labor/delivery 2) Relaxation/Breathing Techniques 3) Labor Coach: Partners help to learn how to relax, massage, and encourage the delivering mothers
Stages of Childbirth
1) Dilation and effacement of the cervix 2) Delivery of the baby 3) Delivery of the placenta
What are the three periods of pregnancy?
1) The Germinal Period 2) The period of the embryo 3) The period of the fetus
Natural, or prepared, childbirth
A group of techniques aimed at reducing pain and medical intervention and making childbirth a rewarding experience
Most common approach for labor pain: Epidural Analgesia
A regional pain-relieving drugs that is delivered continuously through a catheter into a small space in the lower spine --Limit pain reduction to the pelvic region --Some negative effects: weakens contraction, labor may take longer, newborns at risk for respiratory stress, etc
Anesthetics
A stronger type of painkiller that blocks sensation
Fetal Alcohol Spectrum Disorder (FASD)
A term that encompasses a range of physical, mental, and behavioral outcomes caused by prenatal alcohol exposure --Children are given one of three diagnoses:
Group Prenatal Care
After each medical checkup, trained leaders provide ethnic minority expectant mothers with a group discussion session, which is conducted in their native language and encourages them to talk about important health issues
Diagnosis 2: Partial Fetal Alcohol Syndrome (p-FAS)
Characterized by: A) two of the three facial abnormalities mentioned (defects of the eyes, ears, nose, throat, heart, etc) B) Brain injury, again evident in at least 3 areas of life
Diagnosis: Fetal Alcohol Syndrome (FAS)
Distinguished by A) slow physical growth, B) a pattern of three facial abnormalities, C) brain injury, evident in a small head and impairment in at least 3 areas of functioning (memory, language, communication, etc)
Analgesics
Drugs used to relieve pain --May be given in mild doses during labor to help a mother relax
The Period of the Embryo
Lasts from implantation through the eighth week of pregnancy --During these brief 6 weeks, the most rapid prenatal changes take place as the groundwork is laid for all body structures and internal organs
The period of the fetus
From the ninth week to the end of pregnancy, is the longest prenatal period
Diagnosis 3: Alcohol-related neurodevelopment disorder (ARND)
In which at least 3 areas of mental functioning are impaired, despite typical physical growth and absence of facial abnormalities --Less pervasive than in FAS
Father Changes around birth
Increase in prolactin - a horse that stimulates milk production in females Increase in estrogen - sex harmed produced in larger quantities in females Drop in androgens (sex hormones produced in larger quantities in males)
Bacterial and Parasitic Diseases
Most common: toxoplasmosis, caused by a parasite found in many animals --may be infect through gardening, eating undercooked meat, etc --If it hits in first trimester: causes eye and brain damage --later infection: mild visual and cognitive impairment
Cervix
Opening of the uterus
Freestanding Birth Centers
Permit greater maternal control over labor and delivery, including choice of delivery positions, presence of family members/friends, and early contact between parents and baby
First Semester: Fetus (9-12 weeks) - Chart
Rapid increase in size --Nervous system, organs, and muscles become organized and connected, touch sensitivity extends to most of the back --New behavioral capacities (kicking, thumb sucking, mouth opening, and rehearsal of breathing) appear --External genitals are well-formed, and the fetus's sex = evident
Teratogen
Refers to any environmental agent that causes damage during the prenatal period
Scrotum
Sacs that lie just behind the penis
Reasons for not seeking early prenatal care
Situational Barriers: Difficulty finding a doctor, getting an appointment, and arranging transportation Personal Barriers: Psychological stress, the demands of taking care of other young children, family crises, and ambivalence about the pregnancy Many also engage in high-risk behaviors such as smoking and drug abuse
Neonatal Intensive Care Unit Network Neurobehavioral Scale (NNNS)
Specially designed for use with newborns at risk for developmental problems because of low birth weight, preterm delivery, prenatal substance exposure, or other conditions --Scores are used to recommend appropriate interventions/guide parents
Cesarean Delivery
Surgical birth; the doctor makes an incision in the mother's abdomen and lifts the baby out of the uterus --Used for emergencies, certain breech conditions
Last Half of the First Month: Neural Tube
The ectoderm folds over to form the neural tube, or primitive spinal cord
Second Trimester: (13-24 weeks)
The fetus continues to enlarge rapidly --Mom can feel fetal movements --Vernix and lanugo keep fetus skin from chapping in the amniotic fluid --Most of the brain's neurons are in place by 24 weeks --Eyes are sensitive to light, and the fetus reacts to sound
Maternal Factors: Age
The older the mother, the greater the risks --Lower birth weight, greater chance of fetal death, etc
Cerebral cortex
The seat of human intelligence, enlarges
Corpus Luteum
The spot on the ovary from which the ovum is released --Secretes hormones that prepare the lining of the uterus to receive a fertilized ovum --Shrinks if pregnancy does not occur and is discarded with menstruation
Certified Nurse-Midwives
Those who have degrees in nursing and additional training in childbirth management
Breech Position
Turned so that the buttocks or feet would be delivered first
Testes
Two glands located in the scrotum
Ovaries
Two walnut-sized organs located deep inside a woman's abdomen
Apgar Scale
Used to asses the newborn's physical condition quickly by doctors and nurses --Rating of 0, 1, or 2 on each of the five characteristics (heart rate, respiratory effort, reflex irritability, muscle tone, color) is made at 1 min and again at 5 mins --Combined score of 7 or better indicates the baby is in good condition --Score of 4-6: baby needs some assistance breathing --3 or below: infant is in serious danger, requires medical attention
Maternal Factors: Rh Factor Incompatibility
When the mother is Rh-negative (lacks the Rh blood protein) and the father is Rh-positive, the baby may inherit the father's Rh-positive blood --If even a little of a fetus's Rh-positive blood crosses the placenta into the mom's negative blood, she begins to form antibodies to foreign Rh protein --If these enter the fetus's system, they destroy red blood cells, reducing oxygen to tissues and organs --Causes intellectual disability, miscarriage, heart damage, infant death
Umbilical Cord
Which first appears as a primitive body stalk and, during the course of pregnancy, grows to a length of 1 to 3 feet --The umbilical cord contains one large vein that delivers blood loaded with nutrients and two arteries that remove waste products
Lanugo
White, downy hair that appears over the entire body, helping the vernix stick to the skin
About once every 28 days, in the middle of a woman's menstrual cycle...
an ovum bursts from one of her ovaries and is drawn into of the two fallopian tubes