Teratogens

What are the characteristics of babies with FAS?

Below average height and weight
Abnormal facial features
Varying degrees of mental retardation
Behavioural problems

What does smoking during pregnancy lead to?

Significant decrease in birth weight
Increased risk of miscarriage
Developing gastrointestinal problems in childhood
Higher incidence of respiratory problems

What are some pathogens that act as teratogens?

Syphilis
Rubella
HIV
Toxoplasmosis
X-rays

What effect does syphilis have to a child?

Nerve deafness
Cardiovascular defects

What effect does rubella have to a child?

Cataracts
Deafness
Mental retardation

What effect does toxoplasmosis have to a child?

Spinal abnormalities
Brain swelling

What are teratogens?

Substances that cause mutations in somatic cells of developing embryos

What are examples of teratogens?

Antibiotics
Oral anticoagulants
Thyroid drugs
Thalidomide

What are the effects of teratogens?

Interferes with cellular processes (e.g. growth or development)
Cause mutations in cell DNA

What factors affect the severity?

Strength of dosage
Length of time or frequency of exposure
Genetic susceptibility
Stage of pregnancy

What stage of pregnancy is teratogens especially dangerous?

First trimester (week 1-13) as embryonic stem cells are being programmed and building tissues for foetus

What teratogens are dangerous at any stage of pregnancy?

Alcohol and HIV

What is thalidomide?

Drug prescribed to prevent morning sickness in early stages of pregnancy

What does thalidomide do to a baby?

Sharp increase in incidence of limb malformations - acts on 4-6 week old embryo when limbs are forming

Why does thalidomide affects arms more?

Arms form first

What is foetal alcohol syndrome (FAS)?

Group of birth defects that occur in children whose mothers drank alcohol during pregnancy

What does alcohol impact in a baby?

Nervous system

What has a strong link to smoking during pregnancy?

Sudden infant death syndrome (SIDS)

What are pathogenic teratogens?

Pathogens which cause mutations in developing embryos

What effect does HIV have to a child?

HIV