Teratogens Flashcards
What are the teratogenic effects of maternal PKU elevated Phe levels
ID in 90% (if mat levels of Phe are consistenltly over 360umol/L), poor behavioral outcomes, CHDs, Tracheoesophageal fistula, CL +/- CP, IUGR, microcephaly (67% of fetuses if levels not controlled by 30wks)
What are the teratogenic effects of smoking/nicotine
IUGR, low birth weight, premature delivery 2x as frequent, conotruncal and atrioventricular septal defects, urinary tract anomalies, behavioral problems, chronic fetal hypoxia, small brain volumes
What are the teratogenic effects of alcohol
most common cause of cognitive deficiency
microcephaly, short palpebral fissures, epicanthal folds, maxillary hypoplasia, short nose, thin upper lip, abnormal palmar creases, joint defects, IUGR, congenital heart dz, cognitive deficiency
What are the teratogenic effects of androgens/progestogens
may affect the FEMALE fetus, producing masculinization of the external genitalia
in critical period (4-8wks, during organogenesis), increased prevalence of CHDs and glandular hypospadias
possible associated between birth control pills and VACTERL association
What are the teratogenic effects of tetracyclines (doxycycline)
cross placental membrane and deposited in embryo’s bones and teeth at sites of active calcification
exposure during the 4th-9thmo of pregnancy causes enamel hypoplasia, yellowish/brown discoloration of teeth, diminished growth of the long bones
What are the teratogenic effects of Warfarin
cross the placental membrane and may cause hemorrhage in the embryo or fetus (bc it’s an anticoagulant)
hypoplasia of the nasal cartilage, stippled epiphyses, various CNS defects, cognitive deficiency, optic nerve atrophy, microcephaly
critical period btwn 6-12wks post-fertilization
HEPARIN IS NOT TERATOGENIC
What are the teratogenic effects of trimethadone
anticonvulsant
prenatal and postnatal growth delays, DD, V-shaped eyebrows, low set ears, cleft lip/palate, cardiac, genitourinary, and limb defects
What are the teratogenic effects of phenytoin
anticonvulsant
IUGR, microcephaly, cognitive deficiency, ridged frontal suture, inner epicanthal folds, ptosis, broad depressed nasal bridge, nail and distal phalangeal hypoplasia, hernias
What are the teratogenic effects of valproic acid
anticonvulsant
craniofacial defects, CHDs, limb defects, postnatal cognitive DD, NTDs (specifically spina bifida cystica)
phenobarbital, magnesium sulfate, and diazepam appear to be safe in pregnancy
What are the teratogenic effects of aminopterin
antineoplastic agent; folic acid antagonist; inhibit mitosis in rapidly dividing cells
exposure in embryonic period often results in intrauterine death of embryos; 20-30% of those that survive are severely malformed
What are the teratogenic effects of methotrexate
folic acid antagonist; derivative of aminopterin
miscarriage, NTDs, major and multiple skeletal, brain, and other birth defects
What are the teratogenic effects of angiotensin-converting enzyme (ACE) inhibitors
antihypertensive
oligohydramnios, fetal death, hypoplasia of the bones of calvaria, IUGR, cardiovascular abnormalities, renal dysfunction
during early pregnancy, risk to embryo is apparently less
What are the teratogenic effects of isotretinoin/retinoic acid/accutane
critical period: 3rd-5th wk
risk of SAB and birth defects after exposure is high
craniofacial dysmorphism, microtia, micrognathia, cleft palate, thymic aplasia, CHDs, NTDs, significant neuropsychological impairment
What are the teratogenic effects of thalidomide
tranquilizers
meromelia, amelia, rudimentary limbs, micromelia, phocomelia, absence of external and internal ears, hemangioma on the face, CHDs, anomalies of urinary and alimentary systems
critical period: 20-36d post ferilization
What are the teratogenic effects of lithium carbonate
psychotropic drug
Ebstein anomaly (malformation of the tricuspid valve between the right upper and lower heart chambers.
The valve does not properly close, leading to blood flow that may leak back from the lower to upper chambers on the right side of the heart. This can result in significant enlargement of the right heart chamber), defects of the heart and great vessels
What are the teratogenic effects of SSRIs
slightly increased risk for ASDs/VSDs, persistent pulmonary HTN, neurobehavioral disturbances (ASD), preterm labor, temporary neonatal jitteriness, irritability
What are the teratogenic effects of carbamazepine
ASM
NTDs, CHDs, cleft lip, microcephaly, small nose, long philtrum, small finger and toenails, low vitamin K levels in fetus causing bleeding problems
What are the teratogenic effects of cocaine
low birth weight, shorter in length at birth, microcephaly, preterm labor, placental abruption, withdrawals at birth irritability, tremors, muscle stiffness, poor feeding, trouble sleeping, hyperactivity for wks after birth
What are the teratogenic effects of misoprostol/Cytotec
med used for tx of stomach ulcers and those at risk
vascular disruption, missing parts of digits/toes/arms/legs, Moebius syndrome (weakness/paralysis of facial muscles), cleft lip with or without cleft palate, arthrogryposis, muscle weakness, club foot
What are the teratogenic effects of methimazole
anti-thyroid med to tx hyperthyroidism
cases of renal, skull, CHDs, exomphalos, GI malformations, umbilical malformations, and duodenal atresia
What are the teratogenic effects of cytomegalovirus
infects placenta, then the fetus; fetuses are often born immature
most affected pregnancies spontaneously abort when infections occur in 1st tri
1 in 200 babies are born w congenital CMV and 1/5 are symptomatic
neonates infected early on: no clinical signs; asymptomatic cases often associated with audiologic, neurologic, and neurobehavioral disturbances post-birth
infections later in pregnancy: DD, IUGR, microphthalmia, chorioretinitis, blindness, microcephaly, cerebral calcification, cognitive deficiency, deafness, cerebral palsy, hepatosplenomegaly, seizures
What are the teratogenic effects of hepatitis B
if mom is infected, baby can have up to a 90% chance of being affected
causes progressive liver dz, cirrhosis, or liver ca by 5yo
need to be put on meds immediately after birth if +
What are the teratogenic effects of herpes simplex virus
increased SAB rate by 3-fold
infections after the 20th wk associated with: increased rate of prematurity, cutaneous lesions, microcephaly, microphthalmia, spasticity, retinal dysplasia, cognitive deficiency
if exposed during birth can develop severe CNS and organ damage
What are the teratogenic effects of human parvovirus B19 (Fifth’s dz)
33% chance of passing infection to baby, 10% chance there will be complications
myocarditis, aplastic crises, anemia, hydrops fetalis, fetal loss
What are the teratogenic effects of rubella
crosses placental membrane, 20% chance of embryonic/fetal infection if mom is infected
cataracts, blueberry muffin rash, salt and pepper retinopathy, CHDs, deafness, cognitive deficiency, chorioretinitis, glaucoma, microphthalmia, tooth defects
infections leading to defects typically occur btwn 4-5wks embryonic age when organogenesis occurs
What are the teratogenic effects of zika
caused by Aedes mosquito
microcephaly, other brain abnormalities
What are the teratogenic effects of varicella
if infection occurs in the 1st 2 trimesters:
skin scarring, muscle atrophy, hypoplasia of the limbs, rudimentary digits, eye, and brain damage, cognitive deficiency, ventriculomegaly
after 20wks GA, no teratogenic risk
What are the teratogenic effects of toxoplasmosis
intracellular parasite can be found in the bloodstream and tissues or endothelial cells, leukocytes; mat infection caused by: eating raw or poorly cooked meats, close contact with infected domestic animals (cats) or infected soil
crosses placental membrane to infect fetus causing: intracranial calcifications, chorioretinitis, cognitive deficiency, microcephaly, microphthalmia, hydrocephaly, fetal death
What are the teratogenic effects of syphilis
~40% of babies born to ppl w untx syphilis may be stillborn or die from the infection
can infect as early as 6-8wks of development
primary mat infections (acquired during pregnancy) usually result in: congenital deafness, abnormal teeth and bones, hydrocephalus, cognitive deficiency, destructive lesions of the palate and nasal septum (Hutchinson teeth), snuffles, saber shins, frontal bossing, saddle nose, poorly developed maxilla
in secondary infections (acquired BEFORE) in which mom goes untx, 80% will deliver an abnormal fetus
What are the teratogenic effects of HIV
Increased SAB rate 3x; infection of fetus usually occurs very late in pregnancy
cutaneous lesions, microcephaly, microphthalmia, spasticity, retinal dysplasia, cognitive deficiency
What are the teratogenic effects of maternal diabetes
increased rate of spontaneous miscarriage, 2-3x incidence of birth defects
macrosomia, prominent fat pads on upper back and lower jaw, brain anomalies, skeletal defects, sacral agenesis, CHDs, metabolic complications, respiratory distress syndrome
What are the teratogenic effects of maternal obesity
CHDs, ONTDs, macrosomia
What are the teratogenic effects of mercury
from too much fish
fetal Minamata syndrome (neurologic and behavioral disturbances resembling cerebral palsy), severe brain damage, cognitive deficiency, blindness, cerebral atrophy, spasticity, seizures
What are the teratogenic effects of radiation
recommended limit is 500mrads; severity of the embryonic damage is related to the absorbed dose of radiation, the dose rate, and the stage of fetal development when exposure occurs (critical period betwn 8-16wks post-fertilization)
growth restriction, microcephaly, spina bifida cystica, pigment changes of the retina, cataracts, cleft palate, skeletal and visceral abnormalities, cognitive deficiency, hydrocephaly, anencephaly, anotia, colon atresia
What is the all or nothing period
exposure in the first four weeks after fertilization will either cause failure to implant/early miscarriage due to cell damage OR won’t cause any developmental issues bc development hasn’t yet occurred
embryo implants in uterus in SECOND week of pregnancy
It is technically 4wks after your last period ended OR two weeks GA
How are TORCH titer results interpreted
results will include values associated with the presence/absence of IgM or IgG antibodies
IgM antibodies present: indicates a recent infection, there is a risk to baby bc a recent infection could have been during pregnancy
IgG antibodies: from a past infection or vaccination (likely before pregnancy)
When should TORCH titers be ordered? What samples would you need?
IUGR, microcephaly, intracranial calcifications, hearing loss, seizures, cataracts
done on infant blood, maternal blood, or amniocentesis sample
