1. Birth Defects

2. Birth Defects
An abnormality that affects the structure or function of the body.
Everyone is born with some type of imperfection (birthmark for example).
Birth defects are children born with more serious problems.

3. Causes of Birth Defects
Heredity
Inherited from one or both parents
Environment
Controllable factors in the environment
A combination of both heredity and the environment.

4. Environmental Influences
Harmful substances taken by the mother
Over-the-counter medications
Prescription medications
Illegal drugs
Tobacco
Alcohol

5. Environmental Influences
When the mother consumes harmful substances, the following can happen to the fetus:
Slow the fetal growth
Cause low birth weight babies
Varying levels of mental retardation
Malformations

6. Environmental Influences
Diseases or infections from the mother
Toxoplasmosis
Hepatitis C
HIV and AIDS
Fifth disease
Chickenpox
Cytomegalovirus
Group B streptococcus
Rubella (German measles)
Influenza

7. Helping to Prevent Birth Defects
Avoid exposure to X-rays, pollutants, and toxic substances.
Get appropriate rest and follow stress management techniques.
Age of the mother
Risk for genetic birth defects increase if the age of the mother is over 35.
Example – Down Syndrome

8. Helping to Prevent Birth Defects
Seek early and continual medical attention/prenatal care.
Early = By the 13th week of pregnancy
Continual = At least 13 total visits over the course of 40 weeks of pregnancy.
Maintain a proper diet.
The placenta does not transfer essential nutrients to the fetus if a woman is undernourished.

9. Helping to Prevent Birth Defects
Exercise
Walking and swimming
Appropriate weight gain
24-30 pounds during pregnancy.

10. Helping to Prevent Birth Defects
Receive proper immunizations prior to becoming pregnant.
Receiving the Rubella vaccine may be dangerous for women who are pregnant.
Do not contract an STD/STI
Those infections are passed onto the fetus.

11. Folic Acid Helps to prevent neural tube defects.
Women of childbearing age who have inadequate folate intakes are more likely to give birth to babies with neural tube damage.
400 micrograms of folic acid daily from supplements or fortified foods is recommended.

12. Folic Acid
Neural tube damage occurs during the first weeks of pregnancy before a woman may realize she is pregnant.
This may be prevented as a mother takes folic acid prior to conception.

13. Detecting Birth Defects
Ultrasound
Utilizes sound waves to detect the health and development of the fetus.
Amniocentesis
Inserting a needle through the abdominal wall and into the uterus and withdrawing some amniotic fluid to detect birth defects.

14. Method of Inheritance Recessive Inheritance Dominant Inheritance
Multi-factorial Inheritance
Chromosomal Error
Congenital Malformation
Blood Disorder
Prenatal Damage
Metabolic Disorder
X-Linked (Sex-Linked)

15. Recessive Inheritance
Both genes in a pair must be defective to cause disease.
People with only one defective gene in the pair are considered carriers.
Examples include:
Sickle cell anemia
Cystic fibrosis

16. Dominant Inheritance
The mutated gene is a dominant gene located on one of the nonsex chromosomes.
You need only one mutated gene to be affected by this type of disorder.
Examples include:
Huntington’s Disease

17. Multi-Factorial Inheritance
Many factors are involved – heredity and environmental
Examples include:
Cleft lip/palate
Club hand/foot
Combination of genes from both parents, in addition to unknown environmental factors, produce the trait or condition.
Neural tube defects
Cerebral Palsy
Muscular Dystrophy

18. Chromosomal Error
The fertilized egg cell contains chromosomes in an abnormal structure, number, or arrangement.
Examples include:
Down’s Syndrome

19. Congenital Malformation
A condition that is present at birth.
Examples include:
Heart defects
Neural tube defects
Extra body parts (such as a finger)

20. Blood Disorder Affect any of the three main components of blood
Red blood cells: Carry oxygen to the body’s tissues
White blood cells: Fight infection
Platelets: Help blood to clot
Examples include:
Hemophilia and Anemia

21. Prenatal Damage
Exposure to harmful agents during critical prenatal development which causes damage to the embryo or fetus before birth.
Examples include:
Fetal alcohol syndrome
STD’s and STI’s

22. Metabolic Disorder
Genetic conditions that result in metabolism problems.
Metabolism: The chemical reactions taking place in the body to convert or use energy.
Major examples of metabolism include:
Breaking down the carbohydrates, proteins and fats in food to release energy.
Transforming excess nitrogen into waste products excreted in urine

23. Metabolic Disorder Major examples of metabolism also include:
Breaking down or converting chemicals into other substances and transporting them inside cells
Examples include:
Tay-Sachs disease
PKU

24. X-Linked (Sex-Linked)
Traits carried on the X chromosomes which makes females the carriers but the defect show up in the males.
Examples include:
Hemophilia
Colorblindness
Muscular Dystrophy

25. Influences on Birth Defects
Heredity
Down’s Syndrome
PKU
Muscular Dystrophy
Colorblindness
Hemophilia
Cystic Fibrosis

26. Influences on Birth Defects
Environmental
Fetal alcohol syndrome (FAS)
STD/STI related

27. Influences on Birth Defects
Combination of Heredity and Environmental
Cleft lip/palate
Club hand/foot
Cerebral palsy
Neural tube defects

28. Summary There are many factors that influence birth defects.
Some you can prevent while others you cannot.
Become aware of what you can do now to prepare to have a healthy child.

29. Birth Defects Presentations
You will split into 12 groups.
Each group will research one birth defect.
You will then present your findings to the class the next time we meet.
The class will take notes from your presentation.