Role of Environment

Question 1

6 adverse environmental effects on reproduction

Answer 1

Infertility
Germ cell mutations
Implantation failure
Embryonic/fetal death/still birth
Growth retardation
Teratogenesis

Question 2

Teratogenic exposure definition

Answer 2

One that can produce a permanent alteration of structure or function in an organism during embryonic or fetal life

Question 3

Main cause of congenital anomaly (apart from multifactorial)

Answer 3

Mendelian disorders

Question 4

Is there such of a thing as a teratogenic agent? Why or why not?

Answer 4

No there isn’t!

Because there are no absolute teratogens, but many agents can exhibit a teratogenic effect under certain circumstances

Question 5

6 factors that affect teratogenicity

Answer 5

Nature of the agent
Dose
Route
Gestational timing
Concurrent exposures
Genetic susceptibility

Question 6

Toluene embryopathy

Answer 6

Mothers who used nail polish to get high could cause teratogenicity in their babies, but not mothers that only used it on their nails
Teratogenicity only in the presence of maternal toxicity!
True of most agents tested in experimental systems

Question 7

Methylene Blue

Answer 7

Shows the importance of route and gestational timing
Given in the aminotic sac to see if there is premature rupture of the membranes or IV for methemoglobinemia
Near term: can cause hemolytic anemia, jaundice
16 weeks: fetal death or intestinal atresia

Question 8

When is the
1. Embryonic
2. Fetal
period?

Answer 8

1. 3-10
2. 11-38
   These are embryological ages (since conception, not LMP)

Question 9

When are ACEIs and ARBs most harmful? What effects do they cause?

Answer 9

2nd or 3rd trimester is the worst

Causes: fetal anuria, oligohydramnios, contractures, pulmonary hypoplasia, neonatal renal failure, death

Question 10

Are teratogens more likely to cause one or many birth defects?

Answer 10

Many

Usually produce characteristic patterns of congenital anomalies

Question 11

5 classes of teratogenic exposures

Answer 11

Maternal metabolic disease
Maternal antibodies
Infections
Physical agents
Drugs and other chemicals

Question 12

4 examples of maternal metabolic diseases that can cause teratogenic exposures

Answer 12

Diabetes mellitus
Obesity
Other endocrinopathies (ex: androgen secreting hormone tumor)
Maternal PKU

Question 13

Mothers with T1D are more likely to have babies with what 2 classes of defects?

Answer 13

Heart defects

Neural tube defects

Question 14

4 examples of maternal antibodies causing effects

Answer 14

Rh disease
SLE
Antiplatelet antibodies
Autoimmune endocrinopathies

Question 15

4 TORCH agents

Answer 15

Syphilis
Toxoplasmosis
Rubella
CMV
TORCH stands for: toxoplasmosis, other, rubella, CMV, herpes simplex

Question 16

5 non TORCH infections that can cause effects

Answer 16

Zika
Varicella
Parovirus
LCMV (lymphocytic choriomeningitis virus)
HIV

Question 17

3 physical agents that can cause effects

Answer 17

Radiation (large doses of ionizing radiation, or radioactive iodine at >13 weeks)
CVS
Early amniocentesis

Question 18

Are environmental toxins big causes of teratogenicity? Why or why not?

Answer 18

Nope

Teratogenic potential of most agents is limited by dose and maternal toxicity

Question 19

5 drugs of abuse that can cause effects (and which one is the main one)

Answer 19

Alcohol (main one)
Cigarette smoking
Cocaine
Marijuana
Opioids

Question 20

Examples of medications that can cause effects

Answer 20

Vitamin A analogs
Anticonvulsants
Cytotoxic drugs
Hormonal agents
Thalidomide
Mycophenolate

Question 21

How can we prevent teratogenic exposures?

Answer 21

Immunization
Physician knowledge
Public education
Regulation
Folic acid supplementation