Human Development Lecture 8 – Teratogens
Teratogens; is the study of abnormal (prenatal) developments
Main principles;
Effects depends on organism; human fetus extremely sensitive, on rats and
rabbits no effect
Effects depends on genetic susceptibility; some are more vulnerable due to
allelic variation in genes
Effects depends on time;
o Zygote period; fluid do not mix with mother’s
o Embryonic period; organs are forming and especially vulnerable
o Fetal period; growth retardation (vertraging) and tissue damage
Effects may be unique to some organs
o Thalidomide; gross limb defects
o Rubella; sensory and internal defects
Likelihood of damage increases with usage (dose-response curve)
Susceptibility is affected by the mother’s physiological state. (age, nutritional
status etc.)
Effects of agent on the mother might be negligible or temporary
Cumulative Risk; Effect may be worse if other risk factors are present (lack of
medical care, poor nutrition, other teratogens)
Type of Teratogen
Pharmacological (drugs)
o Thalidomide; given to pregnant woman to prevent morning sickness
(misselijkheid in de ochtend) during 1e trimester. This is critical period
for limb formation. babies born without long bones of their arms and
legs
Still used today but not during pregnancy
o Aspirin
o Antibiotics
o Diethylstibesterol
o Bisphenol A
o Retinoic Acid (Accutane)
Recreational (drugs of abuse)
o Alcohol; it penetrates the placenta-fetus barrier. Childeren have
attention deficits, language difficulties, learning disabilities, impulsive
behavior, poor judgement
Fetal Alcohol Syndrome (FAS); all the results to have this syndrome
1. Central nervous system problems
2. Low birth weight and height
3. Typical facial features; reduced size of the head, small eyelid openings,
short upturned nose, long upper lip with deficient central groove,
undeveloped outer ear.
Brian features of FAS; can damage the brain, affecting Cerebellum and corpus
collosum (waar thalamus ligt). Midline structures of brain are deficient in
alcohol-exposed mouse embryos, thus defective midline structures in FAS
children.
Teratogens; is the study of abnormal (prenatal) developments
Main principles;
Effects depends on organism; human fetus extremely sensitive, on rats and
rabbits no effect
Effects depends on genetic susceptibility; some are more vulnerable due to
allelic variation in genes
Effects depends on time;
o Zygote period; fluid do not mix with mother’s
o Embryonic period; organs are forming and especially vulnerable
o Fetal period; growth retardation (vertraging) and tissue damage
Effects may be unique to some organs
o Thalidomide; gross limb defects
o Rubella; sensory and internal defects
Likelihood of damage increases with usage (dose-response curve)
Susceptibility is affected by the mother’s physiological state. (age, nutritional
status etc.)
Effects of agent on the mother might be negligible or temporary
Cumulative Risk; Effect may be worse if other risk factors are present (lack of
medical care, poor nutrition, other teratogens)
Type of Teratogen
Pharmacological (drugs)
o Thalidomide; given to pregnant woman to prevent morning sickness
(misselijkheid in de ochtend) during 1e trimester. This is critical period
for limb formation. babies born without long bones of their arms and
legs
Still used today but not during pregnancy
o Aspirin
o Antibiotics
o Diethylstibesterol
o Bisphenol A
o Retinoic Acid (Accutane)
Recreational (drugs of abuse)
o Alcohol; it penetrates the placenta-fetus barrier. Childeren have
attention deficits, language difficulties, learning disabilities, impulsive
behavior, poor judgement
Fetal Alcohol Syndrome (FAS); all the results to have this syndrome
1. Central nervous system problems
2. Low birth weight and height
3. Typical facial features; reduced size of the head, small eyelid openings,
short upturned nose, long upper lip with deficient central groove,
undeveloped outer ear.
Brian features of FAS; can damage the brain, affecting Cerebellum and corpus
collosum (waar thalamus ligt). Midline structures of brain are deficient in
alcohol-exposed mouse embryos, thus defective midline structures in FAS
children.
