teratogenesis Flashcards
Define and describe the stages of human development.
Pre-embryonic Period: fertilization through implantation
Embryonic Period: implantation through gestational week 8
Fetal Period: week 8 through birth (parturition)
Describe the three layers that result from differentiation of the inner cell mass.
endo, ecto, mes, maternal endometrium and the embryonic trophoblast will combine to form the placenta.
is hep b part of torch?
may be, if mom has active hep b during birth so is part of torch syndrome
what can torch cause?
fever difficulties feeding small areas of bleeding under the skin enlargement of the liver and spleen (hepatosplenomegaly) Jaundice hearing impairment abnormalities of the eyes each infectious agent may also result in additional abnormalities that may be variable, depending upon a number of factors (e.g., stage of fetal development).
Define teratogen and give examples.
define: Any Agent That Can Produce a Congenital Anomaly or Raise the Incidence of an Anomaly in the Population
mom exposed, kid get problems (or embryo dies)
examples: cocaine, cigarette smoke,
Compare and contrast the various etiologies of congenital abnormalities.
cocaine: Increased risk of related congenital anomalies resulting from vascular disruption Skull defects Cutis aplasia Porencephaly Subependymal and periventricular cysts Ileal atresia Cardiac anomalies Visceral infarcts
Teratogenicity is Governed by the Principles of Teratology, what are they?
The capacity of an agent to produce birth defects depends on:
- Developmental stage at the time of exposure
- Dose and duration of exposure
- Genotype of the embryo
- Mechanism of action is specific and may involve inhibition of specific biochemical or molecular process (cell death, decreased cell proliferation, or other cellular phenomena)
- Manifestations of abnormal development are death, malformation, growth retardation, and functional disorders
- Access of adverse influences to developing tissues depends on the nature of the agent.
Stages of Development and Effects of Teratogens
Pre-embryonic Period: fertilization through implantation: Kill embryo (spontaneous abortion, which goes unnoticed) –or- the disruptive effects are compensated for by the early embryo.
Embryonic Period: implantation through gestational week 8
Most sensitive period for inducing major birth defects.
Fetal Period: week 8 through birth (parturition)
Teratogen damage is unlikely to produce malformations but can cause death, growth retardation, disruptions or functional deficits.
Teratogenicity is Governed by the Principles of Teratology, what are they?
The capacity of an agent to produce birth defects depends on:
- Developmental stage at the time of exposure
- Dose and duration of exposure
- Genotype of the embryo
- Mechanism of action is specific and may involve inhibition of specific biochemical or molecular process (cell death, decreased cell proliferation, or other cellular phenomena)
- Manifestations of abnormal development are death, malformation, growth retardation, and functional disorders
- Access of adverse influences to developing tissues depends on the nature of the agent.
Embryonic Period: Period time and effects of teratogens
implantation through gestational week 8
Most sensitive period for inducing major birth defects.
Fetal Period: Period time and effects of teratogens
week 8 through birth (parturition)
Teratogen damage is unlikely to produce malformations but can cause death, growth retardation, disruptions or functional deficits.
Cocaine is a _____
Teratogen
Cocaine adverse effects ___
Local vasoconstrictor-adverse effects from vasoconstrictive and hypertensive properties.
High risk of still birth because of vascular disruption (highest risk after the first trimester of pregnancy)
Cocaine Maternal complications:
Maternal complications: MI, arrhythmias, aortic rupture, stroke, seizure, bowel ischemia and sudden death.
Cocaine Exposed embryo is ___
Exposed embryo at higher risk for placental abruption
Cocaine congenital abnormalities increased risk from ___ are __
vascular disruption
Skull defects Cutis aplasia Porencephaly Subependymal and periventricular cysts Ileal atresia Cardiac anomalies Visceral infarcts
Cigarette Smoke Contains Multiple ___ and they are
Nicotine, cotinine, cyanide, thiocyanate, carbon monoxide, cadmium, lead and various hydrocarbons.
Fetotoxic
Vasoactive effects-reduce oxygen levels of baby
Cause of low birth weight (200g less)
Associated with increase of subfertility, spontaneous abortion, placenta previa and abruption, and preterm delivery.
Cocaine congenital abnormalities increased risk from ___ are __
vascular disruption
Skull defects Cutis aplasia Porencephaly Subependymal and periventricular cysts Ileal atresia Cardiac anomalies Visceral infarcts
Fetal Alcohol Syndrome
Behavior disturbances
Brain defects
20% of children with FAS have IQ<70, and 40% have IQ of 70-85.
Cardiac defects
Spinal defects
Craniofacial anomalies
Co-morbid conditions include mental retardation, adhd, learning disorders, sensory impairment, cerebral palsy and epilepsy
Fetal alcohol effect-children who don’t exhibit the entire spectrum of abnormalities.
does Heroin have teratogenic ___ , is associated with ___
No specific teratogenic potential found
Associated with malnutrition of the mother and lack of prenatal care
Associated with use of other illicit drugs with teratogenic potential
Associated with Neonatal abstinence syndrome (NAS)
Excessive Dietary Intake of Vitamin A has Been Associated ___
Teratogenicity,
Avoid unnecessary supplementation of ___ in women of childbearing age, can cause ____
Vitamin A, Can cause malformations involving Cranium Face Heart Central nervous system Thymus
Isotretinoin is a treatment of ___ , can have what kind of issue
cystic acne-one of the most potent teratogens in widespread use.
1st trimester exposure-fetal loss
26-fold increased malformation rate in survivors is similar to that of children exposed to thalidomide
Isotretinoin is a treatment of ___ , can have what kind of issue
cystic acne-one of the most potent teratogens in widespread use.
1st trimester exposure-fetal loss
26-fold increased malformation rate in survivors is similar to that of children exposed to thalidomide
Thalidomide is a ___ that caused ___
Originally developed in the 1950’s for the treatment of pregnancy-associated morning sickness (often used in the first trimester)
Taken off the market because of side effects:
Stunted limb growth resulting in hands and feet being attached close to body, resembling the flippers of a seal (phocomelia)
Blindness
Disfigurement
Cleft palate
Other internal disabilities
Thalidomide is a ___ that caused ___
Originally developed in the 1950’s for the treatment of pregnancy-associated morning sickness (often used in the first trimester)
Taken off the market because of side effects:
Stunted limb growth resulting in hands and feet being attached close to body, resembling the flippers of a seal (phocomelia) Blindness Disfigurement Cleft palate Other internal disabilities
Thalidomide is used today for ____
Used today to treat illness such as multiple myeloma, erythema nodosum leprosum, HIV wasting, aphthous ulcers
