Causes of Death by Age
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Congenital malformations, deformations, and chromosomal anomalies
Disorders related to short gestation and low birth weight
SIDS
Maternal complications of pregnancy
1-4 years Causes of death
Accidents (unintentional Injuries)
Congenital anomalies
Assault (homicide)
Malignant neoplasms
Heart diseases
Causes of death
5-9 years
Accidents (unintentional Injuries)
Malignant neoplasms
Congenital anomalies
Assault (Homicide)
Diseases of the heart
Causes of death 10-14 years
Accidents (unintentional injuries)
Malignant neoplasms
Assault (homicide)
Intentional self-harm (suicide)
Congenital anomalies.
Predisposing factors to birth injuries
– Cephalopelvic disproportion
– Difficult labor (Breech presentation)
– Prematurity
Birth Injuries
• Cranial injuries
– Caput succedaneum
– Cephalohematoma
– Skull fractures
– Intracranial hemorrhage
Birth • Peripheral nerve injuries
– Brachial palsy
– Facial nerve palsy
most common birth injury
Clavicle Fx
22q11.2 Deletion Syndrome
Velocardiofacial Syndrome
Di George Syndrome
Velocardiofacial Syndrome
– Congenital heart disease (outflow tracts)
– Palatal abnormalities/Facial dysmorphism
– Developmental delay
Deletion of 22q11.2
Di George Syndrome
– Thymic hypoplasia – impaired T-cell immunity
– Parathyroid hypoplasia - hypocalcemia
KLINEFELTER‟S SYNDROME
(XXY,XXXY etc.)
– Testicular atrophy • Sterility
– Eunuchoid with:
• Gynecomastia
• Reduced facial, body and pubic hair.
Prone to breast cancer,extragonadal germ cell t., and
autoimmune diseases.
ENVIRONMENTAL
– Maternal/Placental Infections 2-3% of birth defects what infections?
• Rubella
• Toxoplasmosis
• Syphilis
• CMV
• HIV
– The most common congenital malformations
• Cleft lip/palate
• Neural tube defects
Pathogenesis of congenital malformations
1. Timing of the prenatal insult has an important impact on both the occurrence and the type of malformation produced.
2. Genes that regulate morphogenesis may be the target of teratogens.
– Homeobox (HOX) genes
– Sonic hedgehog gene
Sonic Hedgehog Gene defect causes
holoprosencephaly
Cyclopamine causes
holoprosencephaly
Homeobox Gene defect causes
limb, vertebral and craniofacial abnormalities.
Valproic acid mimics what
Homeobox Gene defect
causes valproic acid
Retinoic acid (acne) causes
CNS, cardiac and craniofacial abnormalities including cleft lip and palate. May interfere with TGFβ (palatogenesis)
Malformations
Primary structural abnormality with poor formation of tissue due to a localized error that occurs during development.
Malformations - examples
• Polydactyly& Syndactyly
• Cleftlip
• Cleftpalate
• Congenital heart disease
Disruption
• Structural defect caused by secondary destruction of or interference with a previously normally formed part.
Disruption example
Amniotic bands
entanglement followed by the tearing apart or amputation of a normally developed structure.
– Interruption of blood supply leading to infarction, necrosis, and/or resorption of structures distally.
Deformation
Localized or generalized compression of the growing fetus by abnormal biomechanical forces.
• Arises later in fetal life than do malformations
most common cause of deformation
Uterine constraint
Factors for deformations
Factors –
Maternal
» First pregnancy
» Small uterus
» Leiomyomas
Fetal
Multiple fetuses
Oligohydramnios
Abnormal presentation
Potter Sequence
Oligohydramnios (= lack of amniotic fluid) due to:
• Renal agenesis/ maldevelopment
• Amniotic fluid leak
• Uteroplacental insufficiency
Oligohydramnios causes
• Pulmonary hypoplasia
• Amnion nodosum
• Fetal compression
– Worsens pulmonary hypoplasia
– Breech presentation
– Altered facies
– Positioning defects of feet and hands
