1. Warm Up
List 5 positive health behaviors that a person should practice each day. Circle any that you think would also benefit a developing fetus.

2. The Beginning of the Life Cycle: Fetal Development
Lesson 34

3. Objectives
Explain fetal development from conception through pregnancy and birth
Explain the importance of prenatal care and proper nutrition in promoting optimal health fro both the baby and the mother
Identify the harmful effects certain substances have on the fetus, such as tobacco, alcohol and other drugs
Explain how to access health services early in pregnancy

4. Conception
The entire human body begins as one microscopic cell is formed by the union of an egg cell (‘ovum’ from the female) and a sperm (from the male)
Fertilization: union of a male sperm cell and a female egg cell
Also referred to as conception
Once conception occurs, the resulting cell is called a zygote

5. Implantation The zygote attaches to the uterine wall
As it travels does the fallopian tubes, the zygote divides many times to form a cluster of cells
The cluster of cells that develop between the third and eighth weeks of pregnancy is called an embryo
After the eighth week the developing group of cells is called a fetus
Watch video, CD 2 chapter 19

6. Embryonic Growth
The cells continue to divide, forming three tissue layers that later become various body systems
One becomes the respiratory ad digestive systems
A second layer develops into muscles, bones, blood vessels and skin
A third layer forms the nervous system, sense organs and mouth
Watch video, CD 2 chapter 19

7. Embryonic Growth Continued…
As the embryo grows and develops important structures form outside of it
Amniotic Sac
A thin, fluid filled membrane that surrounds and protects the developing embryo
Insulates the embryo from temperature changes
Umbilical Cord
Ropelike structure that connects the embryo and the mother’s placenta
Placenta
Thick, blood-rich tissue that lines the walls of the uterus during pregnancy and nourishes the embryo

8. Blood supply to mother and embryo are kept separate
However, materials diffuse from one blood supply to the other through the umbilical cord
Nutrients and oxygen pass from the mother’s blood to the embryo
Wastes from the embryo diffuse into the mother’s blood and are excreted from the mother’s body along with her wastes
Substances that are harmful to the developing embryo can pass through the umbilical cord as well
Tobacco, alcohol and drugs must be avoided! No amount is safe!

9. Fetal Development
Time from conception to birth is usually around 9 full months
9 months divided into trimesters, each 3 months long

10. The First Trimester (0-14 weeks)
Zygote may float freely for 48hrs before implanting
Spinal cord grows faster than the rest of the body
Brain, ears and arms begin to form
Heart forms and begins to beat
3-8 weeks
Embryo is about 1 inch long at 8 weeks
Mouth, nostrils, eyelids, hands, fingers, feet and toes begin to form
Nervous system can respond to stimuli
Cardiovascular system is full functional
9-14 weeks
Fetus develops a human profile
Sex organs, eyelids, fingernails and toenails develop
By week 12 the fetus makes crying motions, but no sounds
May suck its thumb

11. The First Trimester

12. The Second Trimester (15-28 weeks)
Fetus can blink
Body begins to grow
Growth of head slows
Limbs reach full proportion
Eyebrows and eyelashes develop
Fetus can grasp and kick and becomes more active
21-28 weeks
Fetus can hear conversations
Regular cycle of waking and sleeping
Rapid increase in weight
Fetus is about 12 inches long and weighs a little more than a pound
May survive if born after 24 weeks, but will require special medical care

13. Second Trimester

14. The Third Trimester (29 weeks to birth)
Fetus uses all five senses
Begins to pass water from the bladder
Some fetuses dream during periods of sleep in the eighth and ninth month of development
Approximately 266 days after conception, the baby weight 6-9 pounds and is ready to be born

15. Third Trimester

16. Preparing for Birth
In the final weeks of pregnancy, the fetus becomes more and more crowded in the uterus, putting increased demands on the mother’s body
Baby’s head moves to the lower part of the uterus (MOST of the time)
Many females experience weak, irregular muscular contractions of the uterus weeks or months before the baby is born
These become regular, stronger and closer together as time approaches for the baby to be born
Stronger contractions induce labor
Final stage of pregnancy in which the uterus contracts, pushing the baby out of the mother’s body

17. Stages of Birth: Leaving the Womb
Stage 1: Dilation
Contractions of the uterus cause the cervix (the opening of the uterus) to dilate (widen)
In 95% of pregnancies the baby’s head is resting on the cervix
Towards the end of this stage, contractions break the amniotic sac that surround the baby “water breaking”
Stage 2:
Passage Through the Birth Canal
Once the cervix is fully dilated, the baby passes through the birth canal
Baby emerges from the mother’s body
Right after the birth takes place, the baby takes its first breath and cries to clear the lungs of amniotic fluid
Stage 3:
Afterbirth
The placenta is still attached to the baby by the umbilical cord
Contractions continue until the placenta “afterbirth” is pushed from the mother’s body
Umbilical cord is cut to separate the placenta from the baby

18. Prenatal Care
Steps that a pregnant female can take to provide for her own health and the health of her baby
Should begins as soon as pregnancy is confirmed

19. Decision 1: Who Will Provide Your Prenatal Care?
Obstetrician: doctor who specialized in the are of female and her developing child
Certified Nurse-Midwife: advanced practical nurse who specializes in prenatal care and delivering babies

20. Decision 2: Where Will the Birth Take Place
Hospital
In the US most births take place here
Home
Birthing Center
Facility in which women with low-risk pregnancies can deliver their babies in a homelike setting
Regardless of where the birth takes place, a doctor or certified nurse-midwife should be present

21. Prenatal Visits Complete physical exam of mother Blood tests
Pelvic exam
Purpose is to identify problems so that they can be corrected or treated as early as possible
Monitor the mother’s weight and blood pressure
Baby viewed with an ultrasound machine

22. Proper Nutrition During Pregnancy
Calcium:
helps build strong bones and teeth
Helps build healthy nerves and muscles
Important in developing heart rhythm
Protein
Helps form muscle and most other tissue
Iron
Makes red blood cells
Supplies oxygen to cells
Vitamin A
Aids in cell and bone growth
Aids in eye development
Vitamin B Complex
Aids in forming the nervous system
Folic Acid
Critical part of spinal fluid
Helps close the tube that contains the central nervous system
Neural tube forms days after conception, so defects can occur before a female even knows she is pregnant. Health care providers suggest that all females of childbearing age consume micrograms of folic acid daily to prevent these defects

23. Weight Gain Only 300 additional calories per day needed
Females at a healthy pre-pregnancy weight should gain only between pounds during pregnancy
Overweight individuals will have to gain less
Underweight individuals should gain more
Physical activity can be beneficial during pregnancy
Make sure to consult with your doctor before going on any exercise program

24. Fetal Health: Dangers Tobacco Alcohol Medicines and Other Drugs
Accounts for up to 30% of low birth weight babies
14% of premature births
10% of infant deaths
Can affect growth, mental development and behavior of child until 11 years old!
Low birth weight, which is a leading cause of death for children under 12 months
These risks apply to pregnant women exposed to second hand smoke as well
Alcohol
Alcohol passes through umbilical cord to fetus
Fetal Alcohol Syndrome (FAS): group of alcohol-related birth defects that includes both physical and mental problems
Serious consequences of FAS: mental retardation, learning disabilities, behavior problems, slowed growth, physical deformities, heart defects
No amount of alcohol is safe
Medicines and Other Drugs
Illegal drugs pose a serious health risk to mother and fetus
Birth defects
Miscarriage
Baby born addicted
Over the counter medication should only be taken with the approval of a doctor

25. Environmental Hazards
Lead
Linked to miscarriages
Low birth weight
Mental disabilities
Behavior problems
Found in paint of house built before 1978 and old pipes may leach it into tap water
Smog
Air pollution
Linked to birth defects
Premature birth
Stillbirth
Infant death
Greatest risk occurs during the second month of pregnancy when most organs and facial features develop
Radiation
Type found in X-rays can affects fetal growth
Mental retardation
Cat litter
Cat feces may contain a parasite that can cause toxoplasmosis
Miscarriage
Premature labor
Other health problems in a newborn
Pregnant females should wash hands after petting a cat, have others clean the litter box and wear gloves if gardening where cats may be present

26. Complications During Pregnancy
Miscarriage
Spontaneous expulsion of a fetus that occurs before the twentieth week of a pregnancy
Still birth
Dead fetus expelled from the body after the twentieth week
Ectopic Pregnancy
Result when the zygote implants in the fallopian tube, abdomen, ovary or cervix
Fetus can’t get nourishment it needs to grow normally
Threat to pregnant female’s life
Number one cause of death of females in the first trimester of pregnancy
Treatment is removal of fetus from the female’s body
Preeclampsia
Also called toxemia
Can prevent the placenta from getting enough blood
Condition may result in low fetal birth weight and problems for mother
Symptoms:
High blood pressure
Swelling
Large amount of protein in the urine
Treatment
Reducing blood pressure through bed rest or medicine
Hospitalization may be necessary