This document discusses pre-natal human development from conception through birth. It describes the stages of development from the germinal period through the fetal period. During these stages, cells differentiate and life support systems develop, organs appear and growth occurs. The document also outlines various teratogens and hazards that can threaten pre-natal development, including prescription drugs, psychoactive substances, environmental toxins, maternal diseases, nutritional deficiencies, and other parental factors. Proper pre-natal care and avoiding hazards can help ensure healthy development.

1. PRE-NATAL
DEVELOPMENT

2. HUMAN LIFE BEGINS AT CONCEPTION
• From conception to zygote, the embryo and the fetus are
undeniably human life.
• The film “Silent Scream”

3. Are you a Pro-abortion or Pro-life?

6. THE STAGES OF PRE-NATAL
DEVELOPMENT
• GERMINAL PERIOD (First 2 weeks after conception)
• A. Creation of zygote
• B. Continued cell division
• C. Attachment of the zygote to the uterine wall
- Differentiation of cells already begins as inner (Blastocyts)
and outer (Trophoblast) layers of the organism are formed.

7. • EMBRYONIC PERIOD (2-8 weeks after conception)
• A. Cell differentiation intensifies
• B. Life support systems for embryo develop
• C. Organs appear
Zygote attached to the wall of the uterus
2 layers of cells are formed
- Inner layer = Endoderm
- Outer layer= Ectoderm & Mesoderm
Organogenesis- Process of organ formation during the first
2months of pre-natal development

8. Life Support System
• Placenta
• Umbilical cord
• Amnion/ amniotic sac

9. • FETAL PERIOD (2months- 7 months after conception)
-growth and development continue dramatically
3 inches long
Wt. 1 ounce
-Active, moves its arms and legs,
opens and closes it’s mouth, moves its
head.
-parts of the face, upper and lower
extremities can be distinguished.
-Genitals can now be Identified.

10. 6 inches long
Wt. 4-7 ounces
-Growth spurt occurs in the
body’s lower parts
-Reflexes are stronger
-Mother feels the movement of
the embryo
-Downy hair (lanugo) covers
body

11. 12 inches long
Wt. close to a pound
- Structure of the skin
(fingernails, toenails are
formed
- More active
- Heartbeat is audible with
ordinary stethoscope

12. 14 inches long
Wt. 1 ½ pound
- Eyes and eyelids are completely
formed
- Fine layer of head covers the
head
- Grasping reflex present
- Irregular movements occur

13. 16 inches long
Wt. 3 pounds
-Cerebral cortex of brain
develops

14. 17 inches long
Wt. 5 pounds
-Subcutaneous fat is
deposited for later use.
-Responds to sounds

15. 21 inches long
Wt. 7 pounds
Organ functions actively
-vernix is present over
the entire body
-position for birth

16. TERATOLOGY AND HAZARDS
TO PRENATAL DEVELOPMENT
• TERATOLOGY- is the field that investigates the causes of
congenital (birth) defects.
• TERATOGEN- Any agent that causes a birth defect.
• From the Greek word tera “monster”

17. CLUSTERS OF HAZARDS TO
PRENATAL DEVELOPMENT

18. I. PRESCRIPTION AND NON-PRESCRIPTION
DRUGS
• ANTIBIOTICS (STREPTOMYCIN AND
TETRACYCLINE)
• DIET PILLS
• ASPIRIN- HIGH DOSAGES

19. 2. PSYCHOACTIVE DRUGS
• ARE DRUGS THAT ACT ON THE NERVOUS SYSTEM TO ALTER STATES OF
CONSCIOUSNESS, MODIFY PERCEPTIONS, AND CHANGE MOODS.
DRUGS
NICOTINE
EFFECTS
Preterm births and low
birth weights, fetal and
neonatal deaths,
respiratory problems,
sudden infant death
syndrome.

20. ALCOHOL
Fetal alcohol spectrum disorders
(FASD)
• facial deformities, defective limbs
and heart
• learning problems and many are
below average in intelligence,
while some are mentally retarded

21. • increased risk of miscarriage
CAFFEINE

22. COCAINE, METHAMPHETAMINE
• higher rates of infant mortality, low birth weight, and
developmental and behavioral problems.
MARIJUANA, HEROIN
• lower intelligence in children, ADHD

23. • RADIATION
• TOXIC WASTES ( CARBON MONOXIDE, MERCURY, LEAD, COAL ASH)
• PROLONGED EXPOSURE TO SAUNAS/ BATH TUBS
3. ENVIRONMENTAL HAZARDS

24. 4. MATERNAL DISEASES
• RUBELLA (GERMAN MEASLES)

25. • SYPHILIS (A SEXUALLY TRANSMITTED INFECTION)
• GENITAL HERPES

26. AIDS
• IS A SEXUALLY TRANSMITTED INFECTION THAT IS CAUSED BY THE HUMAN
IMMUNODEfiCIENCY VIRUS (HIV), WHICH DESTROYS THE BODY’S IMMUNE
SYSTEM. A MOTHER CAN INFECT HER OFFSPRING WITH HIV/AIDS IN THREE
WAYS:
• (1) DURING GESTATION ACROSS THE PLACENTA,
• (2) DURING DELIVERY THROUGH CONTACT WITH MATERNAL BLOOD OR
FLUIDS,
• (3) POSTPARTUM (AFTER BIRTH) THROUGH BREAST FEEDING

27. • FOLIC ACID DEFICIENCY
• NEURAL TUBE DEFECTS
• TWO TYPES
• OPEN NTDS- ANENCEPHALY, ENCEPHALOCELES, HYDRANENCEPHALY,
INIENCEPHALY, SCHIZENCEPHALY AND SPINA BIFIDA.
• CLOSED NTDS- LIPOMYELOMENINGOCELE, LIPOMENINGOCELE AND
TETHERED CORD.
• MATERNAL MALNUTRITION

28. Anencephaly Encephalocele Spina bifida
Open NTDs

29. CLOSED NTDS
Lipomyelomeningocele, Tethered Cord

30. 5. OTHER PARENTAL FACTORS
• EXPOSURE TO LEAD , RADIATION, CERTAIN PESTICIDES AND
PETROCHEMICALS
-MAY CAUSE ABNORMALITIES IN THE SPERM THAT LEAD TO MISCARRIAGE
/ DISEASES SUCH AS CHILDHOOD CANCER.
• OLDER FATHERS MAY PLACE THEIR OFFSPRING AT RISK OF CERTAIN DEFECTS

31. THANK YOU!