Tuesday, January 21, 2014
Teratogen: environmental agent, such as drug, medication, dietary imbalance or
polluting substance that may cause developmental deviations in the growing
human organism; most threatening in embryonic stage
Teratogen effects are exerted mostly during critical periods.
Each different teratogen exerts different effects
Maternal or fetal genotypes interact with these effects. Depending on the
genotypes you may have a more or less severe interaction to a teratogen.
Exert effects largely during critical periods
Each has own effects
Maternal/fetal genotypes may counteract
One’s effects can intensify effects of others
Some may have no effect on mothers
The longer the exposure, the worse it is.
Most serious damage = first 28 weeks in the pregnancy
Environmental Dangersillegal Drugs
Heroin/cocaine & others: withdrawal symptoms in newborn, birth defects
Smoking(nicotine exposure) : leads to low birth weight, increases risk of SIDS (sudden
infant death syndrome), lower IQ, poor school performance, higher risk for dependency
problems later in life.
Preterm infant: born prior to 38 weeks after conception. Weight is appropriate
for gestational age.
Number and severity of problems increase as
Stimulation programmes including massage help offset negative outcomes
Parental contact important for both infants and parents
Longterm effects are dependent on SES and other environmental factors. (Child’s
responsiveness, mother’s competence, family stresses, family and community
Fetal alcohol syndrome: