Chapter 3 Flashcards
Implantation
Occures between 7-9 days. The blastocyst burrows deep into the uterine lining.
Amnion
Membrane that encloses the developing organism in amniotic fluid, which helps keep the temperature of the prenatal world constant and provides a cushion against any jolts caused by the woman’s movement.
Chorion
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 by bringing the embryo’s and mother’s blood close together.
Umbilical Cord
First appears as a primitive body stalk and, during the course of pregnancy, grows to a length of 1-3 feet. The umbilical cord contains one large vein that delivers blood loaded with nutrients and two arteries that remove waste products.
Embryo
The period that lasts from implantation through the eighth week of pregnancy. During these brief weeks, the most rapid prenatal changes take place as the groundwork is laid for all body structures and internal organs.
Neural Tube
The ectoderm folds over to form the neural tube, or primitive spinal cord.
First Trimester
Three prenatal periods:
- ) Germinal
- ) Embryo
- ) Fetus
Germinal Period
1-2 weeks
One-celled zygote multiplies and forms a blastocyst.
The blastocyst burrows into the uterine. Structures that feed and protect the developing organism begin to form - amnion, chorion, yolk sac, placenta, and umbilical.
Embryo Period
3-4 & 5-8 weeks.
A primitive brain and spinal cord appear. Hear, 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.
Fetus Period
9-12 weeks.
Longest prenatal period. “Growth and Finishing” phase.
Rapid increase is size begins. Nervous system, organs, and muscles become organized and connected, touch sensitivity extends to most of the body, and new behavioral capacities (kicking, thumb sucking, mouth opening, and rehearsal of breathing) appear. External genitals are well-formed, and the fetus’s sex is evident.
Second Trimester
13-24 weeks.
The fetus continues to enlarge rapidly. In the middle of this period, the mother can feel fetal movements. Vernix and lanugo keep the fetus’s 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.
Third Trimester
25-38 weeks.
The fetus has a good chance of survival if born during this time. Size increases. Lungs mature. Rapid brain development, in neural connectivity and organization, enables sensory and behavioral capacities to expand. In the middle of this period, a layer of fat is added under the skin. Antibodies are transmitted from mother to fetus to protect against disease. Most fetuses rotate into an upside-down position in preparation for birth.
Vernix
A white cheeselike substance on the skin that protects from chapping from amniotic fluid.
Lanuago
White, downy hair helping the vernix stick to the skin.
Age of Viability
The point of which the baby can first survive. Occurs sometime between 22-26 weeks.
Teratogen
Refers to any environmental agent that causes damage during the prenatal period.
Fetal Alcohol Spectrum Disorder (FASD)
A term that encompasses a range of physical, mental, and behavioral outcomes caused by prenatal alcohol exposure.
Fetal Alcohol Syndrom (FAS)
Distinguished by:
(a) slow physical growth,
(b) a pattern of three facial abnormalities (short eyelid openings; a thin upper lip; a smooth or flattened philtrum, or indentation from the bottom of the nose to the center of the upper lip), and
(c) brain injury evident in a small head and impairment in at least three areas of functioning - for example, memory, language and communication, attention span and activity level (overactivity). planning and reasoning, motor coordination, or social skills.
Partial Fetal Alcohol Syndrome (p-FAS)
Characterized by:
(a) two of the three facial abnormalities just mentioned
(b) brain injury, again evident again evident in at least three areas of impaired functions. Mothers of children with p-FAS generally drank alcohol in smaller quantities, and children’s defects vary with the timing and length of alcohol exposure.
Alcohol-Related Neurodevelopmental Disorder (ARND)
In which at least three areas of mental functioning are in which as least three areas of mental functioning are impaired, despite typical physical growth and absence of facial abnormalities. Again, prenatal alcohol exposure, though confirmed, is less pervasive than in FAS.
Rh Factor Incompatibility
The 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 type. If even a little of a fetus’s Rh-positive blood crosses the placenta into the Rh-negative mother’s bloodstream, she begins to form antibodies to the foreign Rh protein. If these enter the fetus’s system, they destroy red blood cells, reducing the oxygen supply to organs and tissues.
Stage 1 of Childbirth
(a) Dilation and Effacement of the Cervix - contractions of the uterus cause dilation and effacement
(b) Transition - reached when the frequency and strength of the contractions are at their peak and the cervix opens completely
Stage 2 of Childbirth
(a) Pushing - With each contraction, the mother pushes forcing the baby down the birth canal, and the head appears
(b) Birth of the Baby - Near the end of Stage 2, the shoulders emerge, followed quickly by the rest of the baby’s body
Stage 3 of Childbirth
Delivery of the Placenta - With a few final pushes, the placenta is delivered.
Apgar Scale
Used to assess a newborn’s physical condition quickly
Natural (Prepared) Childbirth
A group of techniques aimed at reducing pain and medical intervention and making childbirth a rewarding experience.
Anoxia
Inadequate oxygen supply.
Breech Position
Turned so that the buttocks or feet would be delivered first
Fetal Monitors
Electronic instruments that track the baby’s heart rate during labor.
Cesarean Delivery
Surgical birth; the doctor makes an incision in the mother’s abdomen and lifts the baby out of the uterus.
Preterm Infants
Born several weeks or more before their due date.
Small-For-Date Infants
Below their expected weight considering length of pregnancy.
Reflex
And inborn automatic response to a particular form of stimulation.
Infant Mortality
The number of deaths in the first year of life per 1,000 live births - is an index used around the world to assess the overall health of a nation’s children
States of Arousal
Degrees of sleep and wakefulness.
Rapid-Eye-Movement (REM) Sleep
Irregular state of sleep in which brain-wave activity is remarkably similar to that of the waking state. The eyes dart beneath the lids; hear rate, blood pressure, and breathing are uneven; slight body movements occur.
Non-Rapid-Eye-Movement (NREM) Sleep
Regular state of sleep in which the body is almost motionless, and heart rate, breathing, and brain-wave activity are slow and even.
Sudden Infant Death Syndrome (SIDS)
The unexpected death, usually during the night, of an infant younger than 1 year of age that remains unexplained after thorough investigation.
Visual Acuity
Fineness of discrimination.
Neonatal Behavioral Assessment Scale (NBAS)
Evaluates the newborn’s reflexes, muscle tone, state changes, responsiveness to physical and social stimuli, and other reactions.
T. Berry Brazelton
