1. Prenatal Development
Problems

2. Losing a Baby Miscarriage – before 20 weeks
20% of all pregnancies end in miscarriage
Stillbirth – after 20 weeks
Effects on parents
Feel like they lost a child who was born
Many miscarriages and stillbirths occur naturally

3. Birth Defects 3 out of 100 children in U.S. Vary in degree of severity
Mild to severe
Present at birth to develop months later
Correctible to lifelong
Effect body parts, organs, or systems
Possibility of death

4. Causes of Birth Defects
60% of birth defect origin is unknown
Four main causes
Environment
Hereditary
Chromosome Errors
Interaction of Hereditary and Environment

5. Environmental Causes
All body systems developed within the 1st few weeks
Nutrition
Disease or infection of mother
Harmful substances
Medicines
Outside hazards such as radiation

6. Hereditary Causes 5-6 defective recessive genes per person
2 defective recessive genes = birth defects
1 defective dominant gene = birth defect
Some defective genes only affect one sex
Hemophilia
Color blindness

7. Interaction of Heredity and Environment
Child inherits the tendency for a disease
and
Environmental factors affect development of the child
Similar to a crack in the foundation and then a hurricane or tornado hits, the house is weaker to begin with

8. Errors in Chromosomes Chromosomal defects are not inherited
Result of one extra or one missing chromosome
Most common is down syndrome

9. How does having a child with a birth defect affect the child and the family?

10. Diagnosis/Prevention
Genetic Counseling
Done by family doctors or specialists
Need family medical history
Information on previous pregnancies
Physical examinations
Laboratory tests
Statistical analysis

11. Diagnosis/Prevention
Prenatal Tests
Diagnose more than 100 kinds of birth defects
Three main procedures
Ultrasound
Amniocentesis
Chorionic villi sampling

12. Ultrasound Sound waves produce a video image of the child
Detects skeletal and organ defects
Confirms due date
Detects twins
No risk to baby or mother

13. Amniocentesis Withdraw a sample of amniotic fluid
Detects birth defects and health problems
Down syndrome – mother over 35
Tests the baby’s cells that are in the amniotic fluid using a needle
1 in 200 women with amniocentesis end up miscarrying

14. Chorionic Villi Sampling
Samples tissue from membrane encasing the fetus
Insert tube through the vagina
Snip or suction cells off the membrane
Much higher risk of miscarriage or birth defects
Tests for same diseases as amniocentesis