L12: Teratology Flashcards
Def of Teratology
- Study of abnormal fetal development
Factors Affecting Teratogenecity
- Genetic predisposition
- Route & duration of exposure to teratogen.
- Developmental stage at time of exposure
Factors Affecting Teratogenecity
- Genetic Predisposition
Both maternal & embryonic.
Factors Affecting Teratogenecity
- route & Duration of exposure to teratogen
….
Factors Affecting Teratogenecity
- Developmental stage
Types of Structural Defects
Examples of Teratogenic Agents
A) Drugs & medications
B) Alcohol
C) Ionizing radiation
D) Hyperthermia
E) Maternal medical disorders
F) Fetal infection
Drugs & Meds account for ….. of congenital malformations
<1%
FDA classification of drug teratogenicity
Factors affecting access of drug or medication to fetus
Teratogenic Effects of Tetracycline
Anomalies of teeth & bones.
Teratogenic Effects of Antiepileptic drugs (Phenytoin, Carbamazepine & Valproic acid)
- Most common malformations are cleft lip, cleft palate, congenital heart diseases & NTDs
Teratogenic Effects of Oral anticoagulants (Warfarin)
Skeletal & facial anomalies & Dandy-Walker syndrome
Teratogenic Effects of Danazol & androgen
Virilization of female fetus
Teratogenic effects of Chemotherapeutics (MTX & Cyclophosphamide)
CNS & limb malformations.
Teratogenic Effects of Alcohol
Commonest known teratogenic cause
of MR
alcohol
Teratogenic Effects of Ionizing Radiation
Teratogenic Effects of Ionizing Radiation
- Time of Exposure
Teratogenic Effects of Ionizing Radiation
- Doses
Teratogenic Effects of Hyperthermia
Maternal medical disorders causing teratogenecity
Teratogenic Effects of Syphilis
Teratogenic Effects of Toxoplasmosis
Triad of congenital toxoplasmosis:
▪ chorioretinitis, cerebral calcification & hydrocephalus