Teratogens

Question 1

4 classes of teratogens

Answer 1

radiation, maternal infections, chemicals, and drugs

Question 2

ACE inhibitor

Answer 2

2nd and 3rd trimesters (?), produces a fetopathy by inhibiting fetal urine production, renal dysplasia, renal failure, studies show risk of congenital heart disease and CNS malformations during 1st trimester

Question 3

alcohol

Answer 3

fetal alcohol syndrome (craniofacial abnormalities and neurological damage), exposure during menstrual cycle before conception can induce chromosome segregation errors in ovulated oocyte (aneuploid embryos–spontaneous abortion during 1st trimester)

Question 4

alkylating agents

Answer 4

closely correlated to the DNA alkylation rate of embryonic cells, dose-response

Question 5

aminoglycosides

Answer 5

bactericidal agents, topically/parenterally/nebulised/orally, amikacin, gentamicin, neomycin, streptomycin, tobramycin, ototoxicity and nephrotoxicity, susceptibility to aminoglycoside-induced deafness is genetically determined in some cases, genetic testing for the common predisposing mRNA mutation 1555A>G

Question 6

antiepileptic drugs

Answer 6

congenital heart disease, cleft lip/palate, urogenital defects, and neural tube defects

Question 7

cocaine

Answer 7

GI defects, cardiac defects, tissue death from insufficient blood supply, alkaloid, abrutio placentae, spontaneous abortion, vasoconstriction and hypertension, maternal tachycardia

Question 8

DES (Diethylstilbestrol)

Answer 8

synthestic nonsteroidal estrogen, causes vaginal clear cell adenocarcinoma in daughters, transplacental carcinogen, vaginal adenosis, increased cervical transformation zone, T-shaped uterus, infertility, spontaneous abortion (these are all for the exposed daughters)

Question 9

folate antagonists

Answer 9

neural tube and cardiovascular defects, decreased oxygen consumption

Question 10

iodine

Answer 10

excess can block fetal thyroid function, congenital goiter, readily crosses the placenta

Question 11

isotretinoin

Answer 11

metabolite of vitamin A (retinoic acid), excess can cause cleft lips, ear and eye defects, and mental retardation, stillbirths, fetal disintegrations after 9th week, micrognathia, hydrocephalus, microcephaly

Question 12

lithium

Answer 12

cardiac malformations
increased birth weight
possibly associated with Ebstein anomaly

Question 13

maternal diabetes

Answer 13

early spontaneous abortions, perinatal death, recurrent blastogenic monotopic patterns (holoprosencephaly, caudal dysgenesis, pleiotropic syndromes), most display multiple blastogenic defects of the VACTERL type, predisposition to develop insulin resistance

Question 14

methimazole

Answer 14

minor dysmorphic features, choanal atresia, esophageal atresia, growth retardation, developmental delay

Question 15

methylmercury

Answer 15

neurological issues, effects on nervous system, particularly susceptible during 3rd week of gestation when nervous system begins to form

Question 16

radiation

Answer 16

growth restriction, malformations, impaired brain function, cancer

Question 17

smoking

Answer 17

preterm delivery, low birth weight, SIDS, weak lungs

Question 18

tetracyclines

Answer 18

effects on skeletal formation, during second half of pregnancy can cause permanent yellow-gray-brown discoloration of the teeth and enamel hypoplasia

Question 19

thalidomide

Answer 19

(immunomodulary agent) limb defects, prevents angiogenic outgrowth during early limb formation, loss of immature blood vessels, such vessel loss occurs upstream of changes in limb morphogenesis and gene expression resulting in embryonic death or developmental defects

Question 20

TORCH infections

Answer 20

(herpes simplex/rubella), (Toxoplasmosis, Other agents, Rubella, Cytomegalovirus, Herpes simplex), fever, difficulties feeding, bleeding under skin, hepatosplenomegaly, jaundice, hearing impairment, miscarriage, stillbirth, delayed fetal growth, early delivery

Question 21

warfarin

Answer 21

(Coumadin), fetal warfarin syndrome, low birth weight, slower growth, mental retardation, deafness, small head, malformed bones/cartilage/joints, it blocks the action of vitamin K causing an inhibition of blood clotting factors (leads to internal bleeding of fetus) and osteocalcin (lower bone growth), stillbirth or abortion