1. Chapter 20 Lesson 1 Prenatal Development and Care

2. Prenatal Development
The entire complex human body begins as one cell that is formed by the union of an egg cell and sperm cell
These two cells are microscopic in size
This union is called fertilization
When this occurs it is called a Zygote
When zygote reaches uterus, it has divided many times to from a cluster of cells that has a hollow space in the center
It is called a blastocyst

3. Blastocyst and Zygote

4. Implantation
As the cells of the blasotcyst divide, they begin to implant, or attach to the lining of the uterus, This is called implantation
The cluster of developing cells is called an embryo

5. Embryonic Development

6. Embryonic Development
The cells of the embryo continue to divide, forming three layers of tissue
One layer becomes the respiratory and digestive systems
Another layer develops into muscles, bones, blood vessels, and skin
The third layer becomes at he nervous system, sense organs and mouth

7. Embryonic Development
At the same time, a thin membrane called an AMNIOTIC SAC forms and surrounds the developing embryo. Fluid in the sac acts as a shock absorber that protects the embryo when it is jarred or bumped
A blood rich tissue developed from an outer layer of cells from the embryo and tissue from the mother develops into the PLACENTA

8. Embryonic Development
The embryo is connected to the placenta by the UMBILICAL CORD
The cord carries waste products from the embryo, where they diffuse into the mothers blood

9. Fetal Development
The first 6 weeks

10. Fetal Development
During the first 6 weeks the embryo grows rapidly in length and gains weight
At the start of the third week, it is about ½ to 1 inch long
10,000 times the size of the original cell

11. Fetal Development
At eight weeks the embryo measures about 1 ½ inches long
Fetus – name from the end of 8 weeks until birth
The skin of the fetus is clear and hairless and covered with a waxy protective coating
The fetus contains millions of cells that will arrange themselves into tissues and organs
The brain is one of the first organs to develop
The nervous system grows rapidly and at 9 weeks the head develops
All body systems are now present

12. Fetal Development
Growth of the fetus is rapid during the 4th month, but is slows down in the 5th month
During this time, the mother can feel the fetus move
It may begin to suck its thumb
By the end of the 6th month, the fetus is about 14 inches long

13. Fetal Development
During the last 3 months of pregnancy, the weight of the fetus more than triples
The fetus moves freely within the amniotic sac
The eyes open during the 7th month
During the 9th month the fetus usually moves into a head down position and is ready for birth

14. Fetal Development
1st trimester

15. Fetal Development
2nd trimester

16. Fetal Development

17. Prenatal care
The health of the developing baby is not totally within the control of the mother to be
Heredity, which is will be addressed in the next lesson , is one unavoidable factor that can affect the developing baby
Mother can do much to improve the chances of having a healthy baby

18. Prenatal care
As soon as a female confirms her pregnancy, she should begin to prenatal care
This includes regular visits with an obstetrician or a certified nurse midwife
Physicals, blood tests, and pelvic examinations
Possible problems may be identified and corrected early

19. Prenatal care Nutrition is a special concern
Increased amounts of calcium, vitamin E and iron
Folic acid, such as whole grains and fish, reduces the chance of certain birth defects, such a spina bifada

20. Spina Bifida

21. Medicines, Drugs and Pregnancy
A pregnant female must be very careful about what substances she takes into her body
Babies can be born with addiction to illegal drugs if taken during pregnancy
Caffeine, is another potential hazard to the fetus
It has been linked to birth defects and other problems

22. Alcohol and Pregnancy
Females who drink alcohol during pregnancy may cause permanent damage to the developing baby
Alcohol use by females during pregnancy has been associated with many defects

23. Fetal alcohol syndrome

24. Fetal Alcohol syndrome
Consists of three main features:
Mental retardation
Slow growth before and after birth
Physical defects from cleft palate to hip dislocation

25. Tobacco and Pregnancy A pregnant female must avoid using tobacco
Babies born to tobacco users have a greater chance of being born prematurely with low birth weights
Babies weighing 51/2 pounds or less at birth often develop serious health problems
Low birth weight is the leading cause of death in the first year oflife

26. Tobacco and Pregnancy
Smoking during pregnancy may affect the growth, mental development lane behavior of children at least up to the age of 11
Children of smokers have higher incidence of respiratory problems, such as bronchitis and pneumonia, that do children of non-smokers

27. Stages of Birth Babies are usually born headfirst
In the last few weeks of pregnancy the babies head moves to thelwer part of the uterus
During the birth process the baby is pushed out of the uterus and passes out of the mother’s body
There are THREE STAGES TO BIRTH

28. Stage 1
Dilation – or stretching of the cervix. This results from mild contraction, which are known as labor

29. Stage 2 Passage of the baby through the birth canal –
This is caused by continuing contractions that shorten the uterus

30. Stage 3
Afterbirth- Once the baby is born, contractions continue for another 10 to 15 minutes, ultimately pushing the placenta, now called the afterbirth, out of the mother’s body

31. APGAR TEST
Immediately after birth the hospital administers the APGAR test
It measures the baby’s condition in five areas
1. appearance or coloring
2. pulse
3. grimace or reflex irritability
4. activity
5. repiration

32. Complications during Pregnancy
Miscarriage – Spontaneous abortion – female expels the embryo or fetus
Stillbirth – The birth of a dead fetus