1. Prenatal Development

2. From Conception to Birth
Period of the Zygote
Period of the Embryo
Period of the Fetus

3. The experience of pregnancy
1. Physical complaints such as nausea are common.
2. Normal weight gain is about thirty pounds and is dispersed in organs, baby, and bodily fluid.
3. Changes in the woman's body bring mixed feelings.

4. Period of the Zygote
Begins when egg is fertilized in the fallopian tube.
Period of rapid cell division
Ends 2 weeks later when the zygote is implanted in the wall of the uterus

5. Period of the Zygote

6. Period of the Embryo From 3 to 8 weeks after conception
Body parts are formed during this period
Embryo rests in the amnion filled with amniotic fluid
Umbilical cord joins embryo to placenta

7. Prenatal Structures

8. Period of the Fetus From 9 weeks after conception to birth
Increase in size and systems begin to function
Age of viability: 22 to 28 weeks

9. First Month
By the end of the first month, the embryo is about 1/10 of an inch long. The heart, which is no larger than a poppy seed, has begun beating.

10. First Month

11. Two Months
The embryo is about 1 inch long and has distinct, slightly webbed fingers. Veins are clearly visible. The heart has divided into right and left chambers.

12. Two Months

13. Three Months
By now the fetus is 2 1/2 to 3 inches long and is fully formed. He has begun swallowing and kicking. All organs and muscles have formed and are beginning to function.

14. Four Months
Your baby is covered with a layer of thick, downy hair called lanugo. His heartbeat can be heard clearly. This is when you may feel your baby's first kick.

15. 4 months

16. Five Months
A protective coating called vernix caseosa begins to form on baby's skin. By the end of this month, your baby will be nearly 8 inches long and weigh almost a pound.

17. Six Months
Eyebrows and eyelids are visible. Your baby's lungs are filled with amniotic fluid, and he has started breathing motions. If you talk or sing, he can hear you.

18. 6 Months

19. Seven Months
By the end of the seventh month, your baby weighs about 3 1/2 pounds and is about 12 inches long. His body is well-formed. Fingernails cover his fingertips

20. 7 Months

21. Eight Months
Your baby is gaining about half a pound per week, and layers of fat are piling on. He has probably turned head-down in preparation for birth. He weighs between 4 and 6 pounds.

22. Nine Months
Your baby is a hefty 6 to 9 pounds and measures between 19 and 22 inches. As he becomes more crowded, you may feel him move around less.

24. The birth episode Birth
After about thirty-eight weeks in the womb, the baby is considered "full term," or ready for birth. Fetal presentation refers to the body part closest to the mother's cervix. There are three types of presentation: Cephalic (normal), breech, and transverse.

25. Labor and Delivery
Stage 1: starts when the muscles of the uterus contract and ends when the cervix is fully enlarged (about 10 cm)
Stage 2: baby is pushed down the birth canal
Stage 3: placenta is expelled

26. Stages of labor
1. During the last weeks of pregnancy, it is common for the mother to experience false labor, or Braxton-Hicks contractions.
2. The first stage of labor usually begins with relatively mild contractions, leading to stronger contractions and the dilation of the cervix to accommodate the baby's head (10 centimeters).

27. Stages of labor
3. Toward the end of the first stage, which may take from eight to twenty-four hours, a period of transition begins, and the baby's head begins to move through the birth canal.
4. The second stage of labor is from complete dilation of the cervix to birth, lasting about one to one and one-half hours.
5. During the third stage of labor, which lasts only a few minutes, the afterbirth (consisting of the placenta and umbilical cord) is expelled

28. Three Stages of Labor

29. Birth Complications
Lack of oxygen (anoxia): Often leads to surgical removal of the fetus (C-section)
Premature and Small-for-date infants
Prematurity is less serious than small-for-date

30. Low-birth weight infants
Normal is around 7.5 pounds
Low-birth weight is 5.5 pounds or less
6 or 7 percent of all births in U.S.
At risk for developmental, neurological, and health problems

31. Pre-term Babies Formerly called premature
More than three weeks before due date
At risk for respiratory distress syndrome (RDS)
Extended oxygen use=Retinopathy of Prematurity

32. Problems during labor and delivery (1 of 3)
1. Faulty power is the failure of the uterus to contract strongly enough to make labor progress to an actual delivery. Induced labor can be stimulated by the hormone oxytocin.
2. A faulty passageway condition occurs when the placenta develops so close to the cervix that it blocks the baby's passage down the birth canal during labor. This condition is called placenta previa.

33. Problems with Labor and Delivery (2 of 3)
3. A faulty passenger condition occurs when problems exist with the baby's position or size. Usually babies enter the birth canal head first, but occasionally one turns in the wrong direction during contractions. Forceps sometimes are used to remedy the situation.
4. In a Caesarean section, the mother receives a general anesthetic and the baby is removed surgically. Techniques for this surgery have improved; however, a common criticism is that too many Caesareans are performed.

34. Problems with Labor and Delivery (3 of 3)
To deal with such problems, in most hospitals, electronic fetal monitoring is used to record uterine contractions and the fetal heart rate.

35. Prenatal influences on the child
A. Key concepts
1. Canalization is seen in prenatal development.
2. Drugs and other harmful environmental influences can also canalize development, usually in negative ways.
3. Risk factors can interfere with canalized processes that lead to the development of specific organs.

36. Prenatal health care (1 of 2)
1. Adequate early prenatal health care is critical to infant and maternal health.
2. There are racial differences in adequacy of care.
3. Special programs have been implemented in communities to help high-risk mothers.

37. Prenatal health care (2)
Stress
1. Prolonged anxiety just before or during pregnancy increases the likelihood of medical complications.
2. Emotional stress is related to spontaneous abortion as well as to labor and birthing problems.

38. General Risk Factors
Nutrition: adequate amount of food, protein, vitamins, & minerals
Stress: decreases oxygen to fetus and weakens mother’s immune system
Mother’s Age: neither too young, nor too old

39. Home Factors Teenage Pregnancy
“Babies having babies”--own growth is not complete
Pelvic cradle not ready
Threat to education
Responsibility not yet learned
Maternal malnutrition
Domestic Violence
Seven to Eight percent of pregnant women are beaten by partners; most more than once
High rate of miscarriage

40. Prenatal Diagnosis and Treatment
Diagnosis: ultrasound, amniocentesis, and chorionic villus sampling can detect physical deformities and genetic disorders
Treatment: fetal medicine and genetic engineering are experimental

41. Prenatal Diagnosis
Amniocentesis
Chorionic Villus Sampling

42. Maternal diet and nutrition
1. Poor nutrition leads to specific physical deformities and increased risk for prematurity and infant mortality; later nutritional deprivation leads to a reduced number of brain cells.
2. Pregnant women should eat between two hundred and one thousand calories more per day, adding mainly carbohydrates and protein.

43. Influences on Prenatal Development
General Risk Factors
Teratogens: Diseases, Drugs, and Environmental Hazards
How Teratogens Influence Prenatal Development
Prenatal Diagnosis and Treatment

44. Maternal Diseases (1 of 2)
Rubella, or German measles. Disastrous in first trimester.
Syphilis and gonorrhea. Blindness, jaundice, anemia, pneumonia, skin rash, early death. Silver nitrate in the eyes.
Genital herpes. (1) Disease of skin and mucous membranes, or (2) blindness, permanent brain damage, seizures, and developmental delay.

45. Maternal diseases (2 of 2)
Cytomegalovirus (CMV). High risk for infants; jaundice, microcephaly, deafness, and eye problems.
Toxoplasmosis. Parasite from uncooked meat and cat feces. Low birth weight, enlarged liver and spleen, microcephaly, anemia, and calcifications in the brain.
Pediatric AIDS.

46. Negative Prenatal Influences on the Child
Window of opportunity concept--critical time of vulnerability
Teratogen is any substance or influence that can interfere with or damage a child’s growth

47. Teratogens: Diseases, Drugs, and Environmental Hazards
Many diseases pass through the placenta directly and attack the fetus
Potentially dangerous drugs not limited to cocaine but include alcohol and caffeine
Environmental hazards are treacherous because we’re often unaware of their presence

48. How Teratogens Influence Prenatal Development
Not universally harmful
Harm particular structures at a particular point in development in particular animals

49. Teratogenic Medicinal drugs
Thalidomide is a sedative, also an anti-nausea drug--but deforms children.
Diethylstilbestrol (DES) was used to prevent miscarriages but causes damage to reproductive systems of offspring.
Other potentially harmful prescribed drugs are accutane, streptomycin, and tetra-cycline.

50. Teratogenic non-medicinal drugs (1 of 3)
Marijuana
Active ingredient is tetrahydra-conabaninol or THC
Is stored in fatty tissues of body
Placenta is no barrier
Babies are born with psych. if not physical addiction

51. Effects of Teratogens

52. Heroin An opiate not totally unlike morphine, but more addictive
Severe withdrawal symptoms
Newborn babies of heroin addicts vomit, tremble, cry, and have fever, disturbed sleep, and abnormal cries

53. Fetal alcohol syndrome
CNS damage, heart defects, small head, distortion of joints, and abnormal facial features
Are evident in their inability to pay attention or maintain attention

54. Tobacco
Nicotine and carbon monoxide interfere with fetal oxygen supply
Smoking is associated with low birth weight, spontaneous abortion, higher infant mortality, and poor postnatal adjustment