TERATOGENS
 Teratology – the study of birth defects and their
etiology
 Teratos (Greek) – monster
 Any agent that acts during the embryonic or fetal
stage
 Structural
or
functional
abnormalities
(malformation) in the fetus, or in the child after
birth, as a consequence of maternal exposure
during pregnancy
 Birth defects are known to occur in 3-5% of all
newborns
 Direct damage to fetus, abnormal development
 Ectoderm – forms exoskeleton
o Hair
o Nails
o Skin
 Mesoderm – develops into organs
o Circulatory
o Lungs (epithelial
o Skeletal
o muscular
 Endoderm – forms the inner lining of organs
o Digestive
o Liver
o Pancreas
o Lungs (inner layers)
TYPES OF TERATOGENS
 Natural
o Poisonous plants like skunk cabbage
veratrum, ionizing radiation
 Pharmaceutical
o Thalidomide, tetracycline, streptomycin,
valproic acid, warfarin, diethylstilbestrol,
retinoic acid, penicillin
 Industrial
o Lead methyl, mercury, cadmium, arsenic
 Microbial
o Treponema palladium (syphilis), coxsackie
virus, herpes simplex, rubella (German
measles), cytomegalovirus (CMV)
 Metabolic conditions in the mother
o Diabetes, autoimmune disease (including
Rh incompatibility), phenylketonuria,
dietary deficiencies, malnutrition
 Physical agents
 Metabolic conditions
 Infections
 Drugs
 Chemicals
TORCH
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Toxoplasmosis
Other disease (syphillis)
Rubella
Cytomegalovirus
Herpes simplex
TORCH SCREEN – an immunologic survey that
determine whether these infections exist in either
the pregnant women or the newborn
TOXOPLASMOSIS
 Protozoan infection
 Spread commonly through handling cat stool in soil
or cat litter
 Almost no symptoms except for body malaise and
posterior lymphadenopathy
 May cause CNS damage, hydrocephalus,
microcephaly, intracerebral calcification, retinal
deformities
TOXOPLASMOSIS: PRENATAL DIAGNOSIS
 Placental thickening with a "frosted glass"
appearance
 Cerebral ventricular dilation is usually symmetrical
and bilateral and leads to hydrocephalus
 Hyper-echogenic fetal bowel
 Hepato-splenomegaly and hepatic densities,
pleural, pericardial effusions, and ascites
 If diagnosis is established, serum analysis during
pregnancy
 Sulfonamides is prescribed
 Pyrimethamine-antiprotozoal agent
RUBELLA
 Cause mild rash and mild systemic illness but can
bring devastating effects to the fetus, which
includes
 Deafness
 Mental and motor challenges
 Cataracts
 Cardiac defects (PDS, pulmonary stenosis)
 Retarded IUG
 Thrombocytopenic purpura
 Dental and facial clefts
RUBELLA: MODE OF TRANSMISSION
 Rubella virus is transmitted through person-toperson contact or droplets shed from the
respiratory secretions of infected people.
 Infection can be communicated seven days before
and 4 days after the appearance of the rash
 Rash appears 2-3 weeks following exposure and
persist for three days
 If a woman is infected with rubella during
pregnancy, the virus can cross the placenta and
infect the fetus
RUBELLA: DIAGNOSIS
 Rubella titer (1st prenatal visit)
 Greater than 1:8 – immunity to rubella
 Less than 1:8 – susceptible to viral invasion
 Initially extremely high – recent infection has
occurred
RUBELLA: MANAGEMENT
 A woman who is not immunized before pregnancy
cannot be immunized during pregnancy.
 After immunization, women is advised not to get
pregnant for at least 3 months.
 All women with low rubella titer's should be
immunized to protect against rubella in future
pregnancies.
CYTOMEGALOVIRUS
 Member of herpes virus
 Transmitted through droplet infection from person
to person
 Infant may be born:
o Neurologically
(hydrocephalus,
microcephaly)
o Eye damage (optic atrophy, chorioretinitis)
o Deafness
o Chronic liver disease
o Blueberry muffin lesions
CYTOMEGALOVIRUS: DIAGNOSIS
Isolation of CMV antibodies in serum
CYTOMEGALOVIRUS: PRENATAL USG
 Oligo-hydramnios
 Polyhydramnios
 IUGR
 Fetal ascites, hyperchogenic bowel
 Microcephaly, ventriculomegaly
 Intracranial calcification
 Hepatomegaly
CYTOMEGALOVIRUS: PREVENTION
 Through hand washing before eating
 Avoid crowds of young children
 NO TREATMENT FOR THE INFECTION EXIST
HERPES SIMPLEX VIRUS
 Virus spread into the bloodstream (viremia) and
crosses to the fetus
 Infection takes place in the 1st tri-spontaneous
miscarriage, severe congenital anomalies
 2nd or 3rd tri-premature birth, IUGR
 For women with history of genital herpes and
existing genital lesions, CS birth is often advised to
reduce the risk of neonatal infection
 Intravenous or oral Acyclovir (Zovirax) may be
administered to women during pregnancy
SYPHILIS
 Treponema pallidum
 Extremely damage the fetus after 16th to 18th week
of intrauterine life
 Transmitted via sexual contact
SYPHILIS: DIAGNOSIS
Serologic screening (vdl or plasma reagin) on the 1st
prenatal visit
SYPHILIS: CLINICAL MANIFESTATION
 Fetal:
o Stillbirth
o Neonatal death
o Hydrops fetalis
 Intrauterine death in 25%
 Perinatal mortality in 25-30%
 Early congenital (typically 1st 5 weeks)
o Cutaneous lesions (palms/soles)
o HSM
o Jaundice
o Anemia
o Snuffles
o Periostitis and metaphysical dystrophy
o Funisitis (umbilical cord vasculitis)
 Late congenital:
o Frontal bossing
o Short maxilla
o High palatal arch
o Hutchinson teeth
o 8th nerve deafness
o Saddle nose
o Perioral fissures
 Can be prevented with appropriate treatment
SYPHILIS: TREATEMENT
 Penicillin G – DOC for all syphilis infection
 Maternal treatment during pregnancy very
effective (overall 98% success)
 Treat newborn if
o Mother was treated <4 weeks before
delivery
o Maternal titers do not show adequate
response (less than 4-fold decline)
TERATOGENIC DRUGS (DO NOT TAKE IN FIRST TRIMESTER
OF PREGNANCY)
 ANALGESIC
o Gastroschisis
o Decrease prostaglandin  decrease
uterine contraction  delayed onset of
labor & prolonged period of pregnancy
o During delivery  severe bleeding because
aspirin decrease platelet aggregation
 ANTICONVULSANT
o Fetal hydantoin syndrome
 Cranio-facial malformation
 Cleft lip palate
 Broad nasal bridge
 Abnormal ears
 Congenital heart disease
 Limb malformation
 Mental and growth retardation
 ANTICOAGULANT
o Fetal warfarin syndrome
 Nasal hypoplasia (bones appears
small)
 Bone stippling
 Mental retardation
o Respiratory distress syndrome
o Fetal and maternal hemorrhage
 ANTIDEPRESSANT
 ANTITHYROID
 VITAMIN A
o Retinoic acid embryopathy
 It is a congenital condition caused
by the exposure of the developing
fetus to teratogenic substances
called retinoid. Retinoic acid is a
man-made retinoid derivative of
Vitamin A used to treat cystic acne
and cancer.
o Carnie-facial dimorphism
o Cleft palate (facial malformation)
o Thymic aplasia (missing of organ)
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Neural tube defect (birth defect of brain)
Dental discoloration in children
Maternal hepatoxicity (drug that cause
injury to liver) with large parenteral doses)
ANTIBIOTIC
o Chloramphenicol
 Hypotension
 Cyanosis
 Prevented by using the
drug at recommended
doses and monitoring
blood levels
METAL TOXIC
SEDATIVE/HYPNOTICS
AMINOGLYCOSIDES
o Gentamycin,
streptomycin,
sulfamethoxazole, trimethoprim
o Neonatal hemolysis
o Methemoglobinemia
DO NOT TAKE DURING PREGNANCY
 NICOTINE AND COCAINE
o Both nicotine and cocaine are known to be
addictive
o Developing fetuses become addicted too
o Both drugs constrict blood vessels
o This decreases oxygen delivery to the fetus
o Low birthweight babies, because they
didn’t get enough oxygen to grow
o Newborns going through withdrawals from
drugs
o Most cannot adjust their own body
temperatures
o Neural tube defect
 Problem with the formation of the
brain and/or spinal cord
 Spina bifida
 Myelomeningocele
 ALCOHOL
o Addictive and legal drug
o Beer, wine, liquor – all affect the fetus the
same
o Just as alcohol damages adult brains, it also
damages fetal brains
o Development of facial features change
o Majority of damage with alcohol is due to
consumption during second trimester
o Physical and behavioral deficits can result
 THALIDOMIDE
o Thalidomide was first marketed in 1957 in
West Germany.
o
o
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The German drug company developed and
sold the drug. Primarily prescribed as a
sedative or hypnotic, thalidomide also
claimed to cure "anxiety, insomnia,
gastritis, and tension".
Afterwards, it was used against nausea and
to ease morning sickness in pregnant
women.
Soon, Thalidomide became an over the
counter drug in Germany.
Shortly after the drug was sold in Germany,
between 5,000 and 7,000 infants were
born with Phocomelia (malformation of
the limbs).
Only 40% of these children survived.
Throughout the world, about 10,000 cases
were reported. Only 50% of the 10,000
survived.
Their effects included deformed eyes and
hearts, deformed alimentary and urinary
tracts, blindness and deafness.
Teratogens such as thalidomide, alcohol, vascular
compromise by amniotic bands or other causes, and
maternal diabetes have been reported to cause this severe
limb deficiency. Amelia is a rare condition with an incidence
range from 0.053 to 0.095 in 10,000 live births.
PREGNANCY AND RADIATION EXPOSURE
 Ionizing radiation is the kind of electromagnetic
radiation produced by x-ray machines, radioactive
isotopes, and radiation therapy machines. There is
potential for the embryo or fetus to be exposed
during the diagnostic or therapeutic procedures for
women who are pregnant.
 Most diagnostic procedures expose the embryo to
less than 50 mSv. This level of radiation exposure
will not increase reproductive risks (either birth
defects or miscarriage). According to published
information, the reported radiation dose to
increase the incidence of birth defects or
miscarriage is above 200 mSv.
TERATOGENIC DRUGS (major non-antibiotics)
CAPTAIN
 Corticosteroids
 Androgens
 Progestin & phenytoin
 Thalidomide
 Aspirin
 Indomethacin
MALDIVES
 Methotrexate
 Alcohol & ace
 Lindane
 Danazol
 Iodine radioactive and Isotretinoin
 Valproate
 Efavirenz
 Sulphonamide
TERATOWA
 Thalidomide
 Epileptic medications (valproic acid, phenytoin)
 Retinoid (Vitamin A)
 ACE Inhibitors, ARBS
 Third element (Lithium)
 Oral contraceptives, hormones
 Warfarin
 alcohol