Repro - Embryology (Teratogens) Flashcards
Pg. 554 in First Aid 2014 Pg. 506 in First Aid 2013 Sections include: -Teratogens
During what time frame of pregnancy are embryos most susceptible to teratogens? What is time period called?
Most susceptible in 3rd-8th weeks (embryonic period - organogenesis) of pregnancy
What are the time frames that generally distinguish the extent of teratogenic effects? What are outcomes of teratogens during each of these time frames?
Before week 3: all-or-none effects; After week 8: growth and function affect
What is the effect of ACE inhibitors on a fetus?
Renal damage
What are 2 effects of Alkylating agents on a fetus?
Absence of digits, multiple anomalies
What is the effect of Aminoglycosides on a fetus?
CN VIII toxicity; Think: “A MEAN GUY hit the baby in the ear”
What are 5 effects of Carbamazepine on a fetus?
Neural tube defects, craniofacial defects, fingernail hypoplasia, developmental delay, IUGR (intrauterine growth restriction)
What are 2 effects of Diethylstilbestrol (DES) on a fetus?
Vaginal clear cell adenocarcinoma, Congenital Mullerian anomalies
What is the effect of Folate antagonists on a fetus?
Neural tube defects
What is the effect of Lithium on a fetus?
Ebstein anomaly (atrialized right ventricle)
What is the effect of Methimazole on a fetus?
Aplasia cutis congenita
What is the effect of Phenytoin on a fetus? What 6 symptoms define this effect?
Fetal hydantoin syndrome: microcephaly, dysmorphic craniofacial features, hypoplastic nails and distal phalanges, cardiac defects, IUGR, intellectual disability
What is the effect of Tetracyclines on a fetus?
Discolored teeth; Think: “TEETHracyclines”
What is the effect of Thalidomide on a fetus? Give 2 examples of this effect.
Limb defects (phocomelia, micromelia - “flipper” limbs)
What is the effect of Valproate on a fetus, and why?
Inhibition of maternal folate absorption => neural tube defects; Think: “valproATE inhibits folATE absorption”
What are 4 effects of Warfarin on a fetus?
Bone deformities, fetal hemorrhage, abortion, ophthalmologic abnormalities; Think: “do not wage WARFARe on the baby; keep it HEPpy with HEParin (does not cross placenta)”
Give 13 examples of medications that act as teratogens.
(1) ACE inhibitors (2) Akylating agents (3) Aminoglycosides (4) Carbamazepine (5) Diethylstilbestrol (DES) (6) Folate antagonists (7) Lithium (8) Methimazole (9) Phenytoin (10) Tetracyclines (11) Thalidomide (12) Valproate (13) Warfarin
Name 3 forms of substance abuse that can have teratogenic effects.
(1) Alcohol (2) Cocaine (3) Smoking (nicotine, CO)
What are 2 effects of alcohol on a fetus? What is the name of the related condition?
Common cause of birth defects and intellectual disability; Fetal alcohol syndrome
What are 2 effects of cocaine on a fetus? What obstetric complication is associated with cocaine?
Abnormal fetal growth and fetal addiction; placental abruption
Of what is smoking (nicotine, CO) a leading cause in fetuses/newborns, and where? What are 4 other effects of smoking on a fetus?
A leading cause of low birth weight in developed countries; associated with preterm labor, placental problems, IUGR, ADHD
Besides medications and substance abuse, what are 4 other examples of teratogens?
(1) Iodine (lack or excess) (2) Maternal diabetes (3) Vitamin A (excess) (4) X-rays
What are the effects of Iodine (lack or excess) on a fetus?
Congenital goiter or hypothyroidism (cretinism)
What are 3 effects of Maternal diabetes on a fetus?
Caudal regression syndrome (anal atresia to sirenomelia), congenital heart defects, neural tube defects
What 2 risks are high for fetuses experiencing Vitamin A excess?
Extremely high risks for spontaneous abortions and birth defects (cleft palate, cardiac abnormalities)
What are 2 effects of X-rays on a fetus?
Microcephaly, Intellectual disability
What is important to consider about microbiology and teratogens?
Fetal infections and certain antibiotics can also cause congenital malformations (see the Microbiology chapter).