Chapter 3 prenatal development and birth Flashcards
When does development start?
At conception
Conception occurs when the genetic material of the sperm and egg unite to form a single celled zygote
Varicocele
A condition affecting men in which enlarged veins on their testicles raise the temperature in the testes interfering with sperm production
Endometriosis
A condition affecting women arising when bits of tissue lining the uterus grow outside of the uterus
Artificial insemination
A.k.a. intrauterine insemination
Involves injecting sperm into the uterus
In vitro fertilization
Several eggs are removed from a woman’s ovary and manually combined with sperm in a laboratory
Return to the uterus in hopes that one egg will implant
Prenatal stage
Germinal period
First trimester begins with this.
Last approximately two weeks
Zygote divides many times through mitosis forming blastocyst
Prenatal stage embryonic.
Occurs from 3rd to 8th week after conception
Eyes ears, nose, and mouth take shape and buds appear that will become arms and legs
Prenatal stage fetal
Last from ninth week of pregnancy until birth
Encompasses part of the first trimester and all of the middle and last trimesters
Critical period for three processes of brain development: proliferation, migration, and differentiation
Organogenesis
Time period when every major organ takes shape
Amnion
Watertight membrane that fills with fluid that cushions and protects the embryo
Chorion
Membrane that surrounds the amnion
Attaches route extensions called villi to the uterine lining together nourishment for the embryo
Placenta
Tissue fed by blood vessels from the mother and connected to the embryo by the umbilical cord
Spina bifida
Part of the spinal cord is not fully encased in the protective covering of the spinal column
Anencephaly
Failure to close at the top of the neural tube
Fatal, as main portion of the brain does not develop
Age of viability
When survival of the uterus as possible, if the brain and respiratory system are sufficiently developed
Proximately 23 weeks after conception
At week 25 the survival rate without impairment is about 50%
During the second half of pregnancy
Neurons proliferate
Neurons increase in size
Neurons develop myelin
Heart rate activity and movement become organized as infant states
Fetus moves to the fetal position in preparation of birth
Fetal programming
Environmental events during pregnancy may alter the expected genetic unfolding of the embryo/fetus
Fetal programming
Environmental events during pregnancy may alter the expected genetic unfolding of the embryo/fetus
Teratogen
Any disease, drug or other environmental agent that can harm a developing fetus
Effects are worse during the critical period
Teratogen: Thalidomide
Used to relieve morning sickness in 1950s
Later became clear that there are critical periods for different deformities caused by thalidomide

Teratogen: tobacco
Increased risk of miscarriage
Prematurity, growth, retardation, and small size
Respiratory problems
Cleft lip and cleft pallets
Raises risk of SIDS
Problems with attention, impulsivity, delinquent behavior, and substance abuse
Teratogen: alcohol
Crosses the placenta
Disrupts the normal process of neuronal migration
Can lead to neuronal death
Fetal alcohol syndrome
Teratogens: illicit drugs
Cocaine: spontaneous abortion, premature detachment of placenta, fetal nourishment
Opioids: smaller babies, and early delivery, increase risk of cesarean section delivery and respiratory support, neonatal abstinence syndrome a.k.a. withdrawal
Teratogens: rubella (measles)
Blindness, deafness, heart defects, intellectual disability
Teratogens maternal diabetes
Risk of premature delivery
Still birth or miscarriage
Immature, long development
Large fetal size
Teratogens sTI’s
Aids: can be transmitted to babies, prenatally through the placenta; perinatally blood exchanged by mother and baby; postnatally during breast-feeding
Syphilis: can cause miscarriage, stillbirth, blindness, intellectual disability
Teratogens radiation and pollutants
Radiation: higher than normal rate of intellectual disability, greater incidence of leukemia and cancers
Pollutants: lower birth rate, pre-term birth, impaired intellectual functioning
Teratogens maternal age
A factor related to fetal death
More common under 15 years and over 40 years old
Maternal factors malnutrition
first trimester disruption formation of spinal cord, fewer brains, cells, and still birth
Third trimester, smaller, neurons, smaller brain, and smaller child
Maternal factors obesity
Offspring obesity, and diabetes
Maternal factors stress and anxiety
Prolonged and severe emotional stress and anxiety during pregnancy: faster and more regular heart rate, stunted, prenatal growth, following birth – smaller, more irritable,, more prone to cry
Paternal factors
Older, paternal age: odds of miscarriage are higher, elevated risk of congenital heart, defects, neural tube, defects, and kidney problems; odds of down syndrome higher; risk factor for schizophrenia
Three stages of childbirth
First stage of labor, mother experiences, regular contractions – oxytocin speeds up contraction
Second stage of labor: delivery
Third stage of labor: delivery of the placenta
Anoxia
Oxygen shortage: umbilical cord becomes pinched or tangled, sedatives interfere with babies, breathing, breach presentation
Severe oxygen shortage: memory impairment, cerebral palsy
Apgar test
Assessment of the newborn’s heart rate, respiration color, muscle tone, and reflexes
Migration
The neurons move from their place of origin in the center of the brain to particular locations throughout the brain wire they will become part of specialized functioning units
Differentiation
Transformation of cells. Neurons Evol into our particulate type or function based on where they land following migration.
Perinatal environment
The environments surrounding birth: drugs given to the mother during labor, delivery practices, and the social environment shortly after birth
Neonatal
the events of the first month and how parents might optimize the development of young infants
Kangaroo care
Resting on a parents, chest helps maintain body temperature, heart rate and oxygen levels