Prenatal Development Flashcards
conception
single sperm cell unites with ovum (egg) in female’s Fallopian tube in process called fertilization
germinal period
prenatal development in first 2 weeks after conception, creation of fertilized egg (zygote), cell division, attachment of zygote to uterine wall
blastocyst
inner mass of cells that eventually develop into an embryo (during germinal period)
trophoblast
outer layer of cells that later provides nutrition and support for the embryo (during germinal period)
implantation
attachment of zygote to uterine wall, takes place about 11-15 days after conception
embryonic period
period of prenatal development from 2-8 weeks after conception
endoderm
embryo’s inner layer of cells that will become digestive and respiratory systems (develops during embryonic period)
mesoderm
embryo’s middle layer of cells that will become circulatory system, bones, muscles, excretory system, and reproductive system (develops during embryonic period)
ectoderm
embryo’s outer layer of cells that will become nervous system and brian, sensory receptors (eyes, nose, ears), and skin parts (such as hair and nails), (develops during embryonic period)
amnion
bag or envelope of the embryo that contains a clear fluid in which the developing embryo floats
umbilical cord
contains two arteries and once vein and connects baby to placenta
placenta
disk-shaped group of tissues in which small blood vessels from the mother and offspring intertwine but do not join
organogenesis
process of organ formation during the first 2 months of prenatal development, during which the organs are especially vulnerable to environmental changes
fetal period
lasts 7 months, prenatal period between 2 months and birth in typical pregnancies
viable
a fetus is considered viable at 7 months
neuron
nerve cell which handles info processing at the cellular level in the brain, 100 billion by the time the baby is born
neural tube
forms from ectoderm, closes at top & bottom, birth defects-anencephaly & spina bifida
neurogenesis
generation of new neurons
neuronal migration
cells move outward from point of origin to appropriate locations and create different levels, structures, & regions of the brain
teratogen
any agent that can potentially cause a birth defect or negatively alter cognitive and behavioral outcomes
dose
greater dose of teratogen, greater effect
genetic susceptibility
type/severity of abnormalities caused by a teratogen is linked to mother’s genotype and fetus’s genotype, & male fetuses are far more likely to be affected by teratogens than female fetuses
time of exposure
teratogens do more damage at specific developmental points, and embryonic period is more vulnerable than fetal period
critical period
fixed time period early in development during which certain experiences or events can have a long-lasting effect on development
prescription teratogens
antibiotics, antidepressants, hormones such as progestin and synthetic estrogen, Accutane
nonprescription teratogens
diet pills, high dosages of aspirin
psychoactive teratogens
drugs that act on the nervous system to alter states of consciousness, modify perceptions, and change moods (caffeine, alcohol, nicotine, and illicit drugs like cocaine, methamphetamine, marijuana, and heroine)
caffeine as teratogen
200 mg. or more per day results in increased risk of miscarriage
alcohol spectrum disorders
cluster of abnormalities and problems that appear in the offspring of mothers who drink alcohol heavily during pregnancy
nicotine
adversely affects prenatal, birth, and postnatal development through preterm births, low birth weights, fetal & neonatal deaths, respiratory problems, SIDS, and cardiovascular problems
cocaine
reduced birth weight, length, and head circumference
methamphetamine
high infant mortality, low birth weight
marijuana
lower intelligence, linked to child using marijuana
heroine
withdrawal symptoms: tremors, irritability, abnormal crying, disturbed sleep, impaired motor control; behavioral problems, attention deficits
Rh-factor
present in red blood cells=Rh-positive
mom Rh- + fetus Rh+ = immune system attach
miscarriage, stillbirth, anemia, jaundice, heart defects, brian damage, death soon after birth
environmental teratogins
radiation, toxic wastes, environmental pollutions (carbon monoxide, mercury, lead, fertilizers, pesticides)
Rubella
maternal German measles
Syphilis
sexually transmitted infection, more damaging after 4 months, eye lesions, blindness, skin lesions
AIDs
sexually transmitted infection, human immunodeficiency virus, destroys body’s immune system
diabetes
high levels of sugar in the blood, high birth weights, risk of infant diabetes
maternal risk factors
overweight folic acid (B-complex vitamin) deficiency fish containing mercury maternal age (adolescence, 35 or older) --risk of Down syndrome emotional stress & depression
paternal risk factors
exposure to lead, radiation, pesticides, and petrochemicals, and smoking may cause sperm abnormalities that can lead to miscarriage, diseases such as cancer, early pregnancy loss
prenatal care
defined schedule of medical visits
screening for manageable/treatable diseases
comprehensive educational, social, and nutritional services
3 stages of birth
- longest, contractions dilate cervix to 10 cm
- head starts to move through cervix & birth canal
- afterbirth, placenta, umbilical cord, and other membranes detached & expelled
doula
caregiver who provides continuous physical, emotional, and educational support for mother before, during, and after childbirth
analgesia
used to relieve pain, tranquilizers, barbiturates, and narcotics (like Demerol)
anesthesia
used in late first-stage labor and during delivery to block sensation in an area of the body or to block consciousness
natural childbirth
decreases fear through education, breathing methods, relaxation techniques
prepared childbirth
Lamaze, special breathing technique (Lamaze method) to control pushing in final stages of labor
cesarean delivery
when breech position, baby is removed from uterus through incision in abdomen
alternative birthing techniques
waterbirth, massage, acupuncture, hypnosis, music therapy
Apgar scale
assesses health of newborns at 1 and 5 minutes after birth by evaluating heart rate, respiratory effort, muscle tone, body color, and reflex irritability (each scaled from 0-2 so that total score of 7-10 is good)
Brazelton Neonatal Behavioral Assessment Scale
performed w/in 24-36 hours after birth, used as a sensitive index of neurological competence up to 1 month after birth, assesses neurological development, reflexes, reactions to animate and inanimate stimuli
Neonatal Intensive Care Unit Network Neurobehavioral Scale
assesses newborn’s behavior, neurological and stress responses, regulatory capacities
Low birth weight infants
less than 5.5 lbs.
very low birth weight infants
less than 3.5 lbs.
extremely low birth weight infants
less than 2 lbs.
preterm infants
born 3 weeks or more before pregnancy has reached full term (before 37 weeks of gestation is complete)
small for date infants
birth weight is below normal when length of pregnancy is taken into account
factors contributing to increase in preterm births
older moms, preterm induced labor to increase baby’s survival, increased substance abuse, increased stress
kangaroo care
skin-to-skin contact with baby in diaper only held upright against parent’s bare chest, practiced 2-3 hours per day with preterm infants
postpartum period
period after childbirth lasting approx. 6 weeks until mother’s body has completed adjustment and returned to nearly prepregnant state
involution
process by which uterus returns to prepregnant size 5-6 weeks after birth
postpartum depression
major depressive episode typically occurring around 4 weeks after delivery including strong feelings of sadness, anxiety, or despair
bonding
formation of connection, especially physical bond between parents and the newborn in the period shortly after birth
