PCD—Birth Defects
Objective 3.01
Heredity and Environment Influences
on Prenatal Development
& Long-term Effects on the Health of Children.
FACTS
About 150,000 babies are born each year
with birth defects.
1 out of 28 parents receive frightening
news that their baby has a birth defect.
There are over 4,000 known birth
defects
Birth defects are the leading cause of
death in the first year of life.
What is a Birth Defect?
An abnormality of structure,
function or body metabolism
present at birth that results
in physical or mental
disability or is fatal (deadly).
Prenatal Development
 Influenced by conditions brought on by the
environment and hereditary traits.
 For some of these influences, there are also
birth defects and long-term effects that affect
the health of the child.
 A birth defect is an abnormality that is present
at birth that affects the structure or functions of
the body and may threaten a baby’s health
and/or welfare.
Environment vs. Hereditary
Prenatal Development is influenced by
conditions brought on by the
Environment & Hereditary Traits.
For some of these influences, there are
also birth defects and long-term effects
that affect the health of the child.
Potential Causes
of Birth Defects
 Directions:
 Read Chapter 4.
 Complete the chart on the handout provided using
Chapter 4 Section 3 in the textbook, page 124-125.
 Pick 8 of the 10 Birth Defects
 List the following in the rectangle:
 Causes
 Detections
 Treatments
Environment
Complete the next slides
on the bubble map labeled:
Environmental Influences
Inadequate (not enough)
Nutrition of Mother
 Stunt brain dev.
 Mental retardation
 Increased risk:
multiple birth defects
low birth weight
Rubella, or German measles
 1st trimester of pregnancy can cause severe
birth defects
Blindness
Deafness
Heart disease
Mental retardation
Toxoplasmosis
Parasite causes:
Blindness
Hearing loss
Learning disabilities
Death
Found in cat litter and some raw
meats
Chicken Pox
st
1
During
half of pregnancy:
Scarring of baby’s skin
Limb (arms, legs) defects
Eye problems
Miscarriage
(death before
th
20
week)
STD’s
Can be passed to unborn child
and can lead to:
Serious illnesses
Physical disabilities
Death
Nicotine
Smoking Tobacco
OR
Secondhand Smoke
 Smaller than average babies
 Miscarriages and premature deliveries
 Respiratory infections or allergies
Fetal Alcohol Syndrome
(FAS)
 20% of infants die
 Facial deformities
 Delayed physical growth
 Heart defects
 Hyperactivity
 Mental retardation or disabilities
 Poor coordination
 Difficulty controlling behavior
FAS
Drugs: Over-the-counter & illegal
 Even over-the-counter drugs can potentially cause serious defects if taken




during pregnancy
 Nothing should be taken during pregnancy without doctor’s permission
Pass on drug addition to the baby
 Makes it necessary for baby to go through painful withdrawal period after
birth
Produces severe, long-term learning and behavioral problems
Large amounts of caffeine increase risk of miscarriage
 Low birth-weight babies
 Infant death
Cocaine increases risk of miscarriage
 Produces strokes that lead to brain damage
 Heart attack
 Birth abnormalities
 Death
 Causes tremors, irritability, sleep problems, and developmental delays
Exposure to hazards
 Chemicals
 paint, pesticides, lead-based chemicals, carbon
monoxide, mercury, solvents, paint thinners, and
formaldehyde
 Potentially cause physical and mental abnormalities in
unborn baby
 X rays can cause childhood cancer, miscarriages, and
mental retardation
 Toxoplasmosis
 extreme high blood pressure
Accidental Injuries
 Cerebral palsy
Caused by damage to the brain before,
during, or shortly after birth
 Damage to the developing embryo and fetus
from accidental injuries of all types can
potentially cause a wide range of birth
defects
Hereditary Influences on Prenatal
Development & Birth Defects
Complete the next slides on the bubble
map labeled:
•Hereditary Influences
•Label left side of the paper:
•Defective recessive genes inherited from both
parents
•Label right side of the paper:
•Defective dominant gene inherited from one
parent
Cystic Fibrosis
 Caused by inheritance of recessive genes
 More likely to affect Caucasians than African or
Asian-Americas
Defective recessive genes inherited from both parents
Tay-Sachs Disease
 Inherited disease most common among eastern
European families of Jewish descent
Defective recessive genes inherited from both parents
Sickle Cell Anemia
 Malformed red blood cells that deprive the
body of oxygen and prevalent in AfricanAmericans
Defective recessive genes inherited from both parents
Hemophilia
 Passed on from mothers to sons only
 Prevents blood from clotting
Defective dominant gene inherited from one parent
Huntington’s Disease
 Manifests in adulthood males
 Leads to dementia
Defective dominant gene inherited from one parent
Duchene Muscular Dystrophy
Transmitted by female carriers
Usually affects only males
Defective dominant gene inherited from one parent
Color Blindness
 Usually affects only males
Defective dominant gene inherited from one parent
Errors in Chromosomes
 Problems with the number or structure of chromosomes
 Down syndrome
 Associated with mental retardation
 Increased risk of heart defects
 Leukemia
 Poor muscle tone
 Distinctive physical characteristics
Defective dominant gene inherited from one parent
Hereditary &
Environmental
Birth Defects
Heart Defect
Inherited
Drug use
Virus during pregnancy
Cleft lip/cleft palate
 Gap in upper lip or palate
Cleft Palate
 Sometimes the roof of the
mouth does not completely
close, leaving an opening
that extends into the nasal
cavity.
 The cleft may include
either side of the cavity.
 The abnormality may be
associated with cleft lip or
other syndromes.
Cleft Lip
 Incomplete formation of lips
during fetal development leads
to Cleft Lip abnormality.
 The extent varies from mild to
severe.
 The clefts can be distinguished
into unilateral clefts and bilateral
clefts
Spina Bifida and
Hydrocephalus
 Risk can be reduced by
taking folic acid during
pregnancy
Multiple Births
 The hyper-ovulation gene may be
inherited from the mother
 Leading to fraternal twins
 Primarily influenced by environment
 Twin-to-twin syndrome (TTTS)
 Result of one twin taking nourishment
from the other
 Fertility drugs
Identifying Birth Defects
Birth Defects
_____1. Cerebral palsy
_____2.
_____3.
_____4.
_____5.
_____6.
_____7.
_____8.
_____9.
.
______
Symptoms
A. Tiredness, lack of appetite, and pain
B. Gap in the roof of the mouth
Cleft palate
______ C. Incompletely formed spinal cord
Cystic fibrosis
______ D. Progressive weakness and shrinking of
the muscles
Down syndrome
______
E. Child slow to develop motor skills
Hydrocephalus
______
F. Overly rapid growth of the head
Muscular dystrophy ______ G. Very salty sweat and a cough that
doesn’t go away
PKU
______
Sickle cell anemia ______ H. Affects the body’s ability to properly
use
Spina bifida
______
protein
I. Has an extra chromosome
Answers
Birth Defects
E 1. Cerebral palsy
E
B 2. Cleft palate
B
G 3. Cystic fibrosis
H
I 4. Down syndrome
H
F 5. Hydrocephalus
B
D 6. Muscular dystrophy H
H 7. PKU
.
H
A 8. Sickle cell anemia
H
C 9. Spina bifida
B
Symptoms
A. Tiredness, lack of appetite, and pain
B. Gap in the roof of the mouth
C. Incompletely formed spinal cord
D. Progressive weakness and shrinking of
the muscles
E. Child slow to develop motor skills
F. Overly rapid growth of the head
G. Very salty sweat and a cough that
doesn’t go away
H. Affects the body’s ability to properly
use
protein
I. Has an extra chromosome
POP QUIZ time
What potentially causes
birth defects?
•Genetic and environmental
factors
•60% of birth defects are
currently unknown
•A single abnormal gene
Can birth defects be
prevented?
 Potential causes of most birth
defects are not known, there are
a number of steps a woman can
take to reduce her risk
Help Reduce Risk
Visit a health care provider for a pre-pregnancy check up
 especially if you have health problems
 When pregnant, take daily multi-vitamins, containing B-vitamin
folic acid.
 Avoid:
 Alcohol
 Drugs
 Smoking
 prescription or over-the-counter medications without Dr.
permission!

Can some birth defects be
diagnosed before birth?
•Prenatal tests that can be administered:
•Ultrasound
•Amniocentesis
•Chronic villus sampling
Preventing Birth Defects
Avoid…
oPoor nutrition
oAlcohol
oSmoking
oDrugs
oSTDs
oRubella
oParasites
oRadiation
Experiment
 Crack an egg in a glass jar.
 Fill jar halfway full of rubbing alcohol.
 Observe changes to the egg.
 Write on a sticky note how seeing the changes affects their
thinking.
 Discussion what each item represents and how it relates to a
birth defect.
Simon Birch
1 hour and 53 minutes
 A movie about a very small person; he has
a lot of faith and self-confidence in spite
of the fact that he is physically "different",
he has little family support and he has
health problems.
Birth Defect Group Project
Directions
You will receive a birth defect to investigate
Make aware your findings using a blog on the Internet.
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https://www.blogger.com/start
References can come from your notes, textbook, and Internet to find your
references.

DO NOT COPY YOUR INFORMATION = PLAGERISM!!!!!
Classify your birth defect:

“Environmental”

“Hereditary”

“Both”
Blog should describe the following:

Description

Causes

Detection

Treatment

How it affects the person who has it
Reminders
Good websites to use:
www.kidshealth.org
 No plagiarism
 Not too wordy
 Need at least 3 references
 The Developing Child, Page ______
 www._____________.com
 Third choice is your choice (can be another website or notes)
 Post 3 pictures to illustrate your birth defect
 Email me your final BLOG