1. Chapter 4
Pregnancy and Birth

2. The Prenatal World The Germinal Period The Embryonic Period
First two weeks after fertilization
Blastocyst adheres to uterine wall
Placenta, umbilical cord, and amniotic sac begin to form
The Embryonic Period
Lasts from third to eighth week
Cellular Differentiation occurs3 layers of cellsskin, nervous system, and organs

3. The Prenatal World The Fetal Period Third month to birth
3rd month—sex organs appear; nervous system continues to develop
4th-6th months—peak growing time; fetus moves around; sucking, pushing, etc.
7th month—growth slows; viability reached;
8th-9th months—internal organs and senses finish developing

4. Influences on Prenatal Development
Teratogens=any agents causing abnormalities:
Chemicals: Drugs, chemicals, certain medications, i.e. thalidomide, DES, and common substances, i.e. alcohol, cigarettes
Infectious Diseases: (STORCH)--Syphilis, Toxoplasmosis, Rubella, CMV, Herpes, and AIDS

5. Influences on Prenatal Development
Maternal Influences
Maternal Nutrition and Weight
Normal weight is best
Healthy nutritional habits; Eliminate teratogenic substances from diet
Vitamins

6. Influences on Prenatal Development
Maternal Emotions
Serious stress or depressions may trigger hormones that can cross the placenta
Mood swings considered not dangerous unless prolonged and severe
Data is very inconclusive regarding negative affects on the fetus, but may occur

7. Influences on Prenatal Development
Diagnosing Fetal Problems
Amniocentesis
Alpha-Fetoprotein Test
Fetoscopy
Chorionic Villi Sampling
Ultrasound

8. The Birth Process Stages in the Birth Process
Dilation—cervix dilates to 4 inches in diameter
Expulsion—fetus delivered from mother
The Afterbirth—Placenta discharged

9. The Birth Process Birth Complications Forceps Delivery
Breech Birth—baby born feet first
Cesarean Section—surgical delivery through abdomen
Anoxia—lack of oxygen; can cause brain damage, cerebral palsy, or death
Rh Factor—incompatibility between child’s and mother’s blood after 1st baby when Rh-negative mom has Rh positive baby

10. The Birth Process
The Special Case of Prematurity=baby born before 37 weeks
Causes: maternal infection, multiple births, maternal stress, maternal age (under 17 ys. or over 35 ys.), low socioeconomic status due to poor prenatal care, smoking, alcohol use, maternal medical problems not being controlled adequately