Prenatal Risk FactorsPrenatal Risk FactorsPSY 417PSY 417

Maternal StatusMaternal Status Maternal NutritionMaternal Nutrition

– ProteinProtein– Folic AcidFolic Acid

Maternal DiseasesMaternal Diseases– HIVHIV– DiabetesDiabetes

Prenatal Infections: STORCHPrenatal Infections: STORCH SyphilisSyphilis ToxoplasmosisToxoplasmosis RubellaRubella CytomegalovirusCytomegalovirus HerpesHerpes

TeratogenTeratogen ““toxic” agents that cause toxic” agents that cause

deficits/malformations in the fetusdeficits/malformations in the fetus AAgent that can produce a permanent

alteration of structure or function in an organism exposed during embyronic or fetal life.

Example of a MalformationExample of a MalformationAgent OrangeAgent Orange

ThalidomideThalidomide

There is no such thing as a teratogenic agent.

Many agents can produce a teratogenic

effect under some circumstances.

Nature of the agentNature of the agent

Factors That Influence Factors That Influence TeratogenicityTeratogenicity

Dose Route Frequency of exposure Duration of exposure

Gestational timingGestational timing

Factors That Influence Factors That Influence TeratogenicityTeratogenicity

Concurrent exposures Concurrent illness Genetic susceptibility

– Mother– Fetus

TimingTiming

Multifactorial42%

Unknown37% Chromosomal

3%

Monogenic8%

Teratogens10%

Baird et al. AJHG 42:677, 1988

Birth Defects in Childhood

Teratogens

Birth Defects in Childhood

Birth Defects Caused By Teratogenic Exposures Are

Preventable.

AlcoholAlcohol Fetal Alcohol Syndrome (FAS)Fetal Alcohol Syndrome (FAS)

– confirmed maternal drinking during confirmed maternal drinking during pregnancypregnancy

– pattern of facial featurespattern of facial features– growth retardationgrowth retardation– evidence of CNS disturbanceevidence of CNS disturbance

Fetal Alcohol Effect (FAE)Fetal Alcohol Effect (FAE)

Mechanism of TransmissionMechanism of Transmission

FAS: Brain developmentFAS: Brain development

Facial Features: Facial Features: DysmorphologyDysmorphology

CigarettesCigarettes Low birth weightLow birth weight CNS deficits - LD, AttentionCNS deficits - LD, Attention SIDSSIDS Respiratory problemsRespiratory problems Increased risk for cancerIncreased risk for cancer

CigarettesCigarettes

CocaineCocaine No addictionNo addiction Crack baby mythCrack baby myth PrematurityPrematurity Growth retardation - SGAGrowth retardation - SGA Poorer reflexesPoorer reflexes

Other TeratogensOther Teratogens Radiation - genetic mutations, Radiation - genetic mutations,

malformed organsmalformed organs Aspirin - enamel defectsAspirin - enamel defects

Other TeratogensOther Teratogens RubellaRubella Norman GreggNorman Gregg

– An Australian opthamologistAn Australian opthamologist– In early 1940s, saw many blind infantsIn early 1940s, saw many blind infants– Surveyed his colleagues in SydneySurveyed his colleagues in Sydney– Found 78 blind infants visited doctors that yearFound 78 blind infants visited doctors that year– 68 had been exposed to rubella68 had been exposed to rubella– Published 1941 paper about rubella and infant Published 1941 paper about rubella and infant

blindnessblindness

Rubella continuedRubella continued Norman GreggNorman Gregg

– 1941 paper reported widely in popular press1941 paper reported widely in popular press– When it came out, Gregg got two phone callsWhen it came out, Gregg got two phone calls– Mothers who had rubella during first trimesterMothers who had rubella during first trimester– Infants were not blind but deafInfants were not blind but deaf– Sent others to check the historical recordsSent others to check the historical records– Outbreaks of rubella had regularly been followed Outbreaks of rubella had regularly been followed

by epidemics of infant blindness and hearing by epidemics of infant blindness and hearing problemsproblems

– Thus, learned that rubella is a teratogenThus, learned that rubella is a teratogen– Today – vaccine.Today – vaccine.