Presented by Jeanie Ward

1. Conception And Fetal Development Presented by Jeanie Ward

2. The Jones Mr. and Mrs. Jones are at the clinic for family planning. They are planning on getting pregnant and have questions regarding conception.

3. How does the Female Body Prepare for Conception? Describe the process of maturation of an ovum

4. Menstrual Cycle Hormonal cycle Ovarian cycle Endometrial cycle

5. Maturation of the OvumOvarian Cycle • What is the main function of the following: • Follicular Phase – • Ovulatory Phase – • Luteal Phase

6. Maturation of Ovum

7. How will I know I am ovulating?

8. Signs and Symptomsof Ovulation 1. Body Temperature increase 2. Mittelschmerz 3. Cervical Mucus Changes • Increase in amount • Becomes thin, watery, and clear • Ferning • Stretchable: Spinnbarkheit • Alkaline

9. What happens to Corpus Luteum if I do not get Pregnant?

10. What happens to Corpus Luteum if I become Pregnant?

11. Endometrial Cycle • What is the function of the endometrial cycle?

12. Hormonal Cycle • FSH -- Follicle Stimulating Hormone • Begins Growth and Maturation of graafian follicle • LH -- Luteinizing Hormone • assists in continued growth of graafian follicle • ESTROGEN • responsible for proliferation of endometrium • PROGESTERONE • Pro-gestation. Corpus luteum produces progesterone so endometrium won’t slough

13. “I know that a woman will stop having her periods when she gets • pregnant. • Why does that occur?” Mrs. Jones asks

14. Conception Maturation of Ovum and Sperm Cells • Pregnancy comes about from the union of a female germ cell, ovum with a male germ cell, the spermatozoon.

15. One ovum per month is discharged from the ovary. It is transported into the fallopian tube where it begins its journey through the tube in search for the sperm. Viable for 12- 24 hours

16. Fertilization • How does fertilization occur? • Why are millions of sperm necessary for fertilization to occur?

17. Fertilization • As the sperm swarm around the ova, the Acrosome caps of Sperm release zona digesting enzymes. Zona layer

18. “I have been trying to get pregnant for over a year and my husband had a sperm count done last month. Why is the number of sperm so important, I thought only one sperm enters the egg?”

19. Usually occurs in the distal portion of the fallopian tube • Once sperm penetrates ova, physiological barrier renders the ova impenetrable by other sperm, thus only one sperm enters a single ova • Each contributes 23 Chromosomes making a Total of 46 chromosomes • Sex of baby determined at this time. X =female, Y = male

20. Pre-embryonic Development

21. What changes occur to the Fertilized Ovum as it travels to the uterus?

22. Cellular Multiplication • The fertilized zygote begins its travel through the fallopian tube toward the uterus. • Cell / mitotic division (cleavage) occurs • Morula eventually forms a fluid filled cavity within the cell mass. • Inner solid cell mass is called Blastocyst • Outer cell mass that surrounds the cavity is the Trophoblast

23. Morula Trophoblast Outer layer of cells Placenta Chorion Blastocyst INNER CELL MASS Fetus Amnion

24. Implantation How does implantation take place?

25. Cellular Differentiation At 10 – 14 days of age, the blastocyst or beginning zygote begins cellular differentiation into the primary germ layers. All tissues, organs, and systems develop from these layers.

26. Germ Layers Ectoderm • nervous • skin, hair, nails • sensory organs • Mesoderm • muscle • connective tissue • blood vessels • bone marrow • Endoderm • Genitourinary • Respiratory--larynx, trachea, lungs • Digestive

27. Auxiliary Structures Placenta Fetal Membranes

28. The placenta is one mechanism that the body has in providing protection to the growing fetus? How does this occur? What are other functions of the placenta?

29. Functions of the Placenta • Fetal Respirations • Fetal Nutrition • Endocrine Functions • Elimination of Wastes • Barrier against certain substances

30. Amnion Smooth, glistening membrane know as the AMNION is the lining of a Fluid filled space that develops around the embryo.

31. Functions of Amniotic Fluid • Keeps the fetus at an even temperature • Cushions the fetus against possible injury • Provides place for the fetus to move easily and grow symmetrically • Fetus drinks the fluid

32. Chorion Thick membrane with finger-like projections called chorionic villi. Chorionic villi contain blood vessels that are main connection with mother. Chorionic villi producehuman chorionic gonadotropin (HCG) Merges with the decidua basalis to form the PLACENTA.

33. Umbilical Cord Body stalk that attaches the embryo to the yolk sac Contains blood vessels that extend into the chorionic villi Protected by wharton’s jelly

34. Developmental Periods

35. Development Periods • Stage 1 -- zygote • weeks 1 - 3 • Stage 2 -- embryonic • weeks 4 - 8 • period of ORGANOGENESIS • Stage 3 -- fetal • weeks 9 - 40

36. Embryonic PeriodWeeks 4-8 • Week 4 • anterior end of neural tube closes to form the brain and the posterior end closes to form the spinal cord • Heart begins to beat • Eyes appear • Limb Buds for arms and legs • CR = 4 mm

37. Week 5 • Head grows larger • Hand and feet plates develop • Facial features begin to develop • CR = 8 mm.

38. Week 6 • Fetal circulation is established • Chambers form in the heart • Upper lip and palate start fusing • Eyes move to front of face • Fingers are webbed • External ear develops

39. Week 7 • Eyelids start to form • Fingers develop; elbows visible • Diaphragm separates abdomen from chest • Bronchi develop • Arms and legs move

40. Week 8 • Fingers and toes distinct • Skeletal ossification begins • Testes and ovaries are distinguishable • Heart has four chambers • Circulation through umbilical cord occurs • *** ALL essential external and internal structures are present and now will continue to grow

41. Mrs. Jones tells the nurse that she is worried that the baby may have some defect because she was on antibiotics and other cold medications during the first week after intercourse / conception. What is happening during the first week after conception that would assist the nurse in answering her question?

42. Mrs. Jones returns for her next prenatal check-up at 6 weeks gestation. Mrs. Jones asks what is happening in the development of her baby this week? (sixth week).

43. Fetal PeriodWeeks 9-40 12 weeks 18 weeks 32 weeks gestation 24 weeks 16 weeks

44. Weeks 9-12 Head size increases Face is well formed Nails appear Eyelids appear and close and fuse shut Kidneys excrete urine Intestines are forming; peristalsis begins Heartbeat can be heard via ultrasound Tooth buds appear for the baby teeth

45. Weeks 13-16 Lips form, facial contour develops Ossification of bone begins Meconium begins to form in the intestines Hair present on scalp Sex can be determined visually

46. Weeks 17-20 Hair abundant on head Lanugo covers the body Vernix begins to form Myelination of spinal cord begins Suck and swallow begin Quickening occurs ~ 18 weeks

47. Weeks 21-24 weeks • Respiratory movement with air sacs formed • Surfactant production begins ~ 24 weeks • Brain appears mature • Eyebrows and eyelashes can be seen • Reacts to sudden noise with active movement

48. Weeks 25 - 28 Eyelids open and close Capillaries proliferate around the lungs’ alveoli making gas exchange possible Skin has wrinkled red appearance Rapid brain development

49. Weeks 29- 32 Subcutaneous fat forms Testes start descending Fingernails and toenails are complete Bones are fully developed, but still soft and pliable

50. Weeks 33 - 40 Limbs start to flex Muscle tone is developed Lanugo disappears Body begins to store fat Maternal antibodies transfer to the fetus Exhibits sleep and awake patterns