Mesa Community College
Nursing Process I NUR 108
Childbearing Family Concepts
Anatomy and Physiology of Reproduction
A. Anatomy
B. Phases of the Menstrual Cycle
1. Menstrual phase: (55) first day of menstrual flow is the first day in the endometrial or uterine cycle and marks the beginning of menstrual period.
2. Proliferative (follicular) phase: (55)
Proliferative: the time from cessation of menses until the beginning of ovulation. Enlargement of endometrial glands in response new estrogen stimulation.
Follicular: begins immediately after menses and ends about midway through the uterine cycle. During this phase the follicle matures, with final maturation and release of the ovum, influenced by a surge of LH from the anterior pituitary gland.
3. Secretory (luteal) phase: (55)
Secretory: under the influence of progesterone, the endometrial cells swell and dilate in preparation for the fertilized ovum.
Luteal: begins when the Graafian follicle ruptures and the ovum is released.
4. Ischemic phase: (55) fertilization and implantation have not occurred and results in vasoconstriction, causing a decreased blood supply to the endometrium resulting in tissue breakdown (menstruation).
Sexuality
A. Sexual Response: Cycle divided into four stages (56-57)
1. Excitement
2. Plateau
3. Orgasmic
4. Resolution
Genetics
A. Crossword Puzzle (Collaborative learning exercise)
Conception/Fertilization
A. The union of a single egg and sperm. Series of events.
1. Gamete: egg and sperm formation
2. Ovulate: release of ovum
3. Union of gamete: egg and sperm join
4. Implantation of embryo in uterus
B. Pregnancy Length
10 Lunar months, 9 calendar months, 40 weeks, or 280 days
1. EDC (estimated date of confinement (EOC): EDB (estimated date of birth)
2. Naegle's Rule: add seven to the first day of the LMP, subtract 3 months, and add 1 year (add 7 days to LMP and add 9 months)
Fetal Development (142-157) Box 7-2
A. Period of the Zygote (stage of the ovum) (135)
Fertilized ovum
B. Period of the Embryo
Conception up to week 10 after the last menstrual period or 8 weeks after fertilization.
C. Period of the Fetus
Offspring from the moment of conception until the pregnancy is terminated or completed.
D. Placenta
The development of the placenta occurs during the third week. The placenta is formed at the site of attachment of the chorion to the uterine wall, and both the placenta and its membranes are completely functional by the 12 week.
1. Endocrine gland: (139-141)
a. Human chorionic gonadotropin (hCG): PG tests for. Sustains pregnancy by preventing the involution of the corpus luteum.
b. Human placental lactogen (hPL): stimulates changes in the mother’s metabolic process to ensure the mother’s body is prepared for lactation.
c. Progesterone: (194-195) the hormone that maintains pregnancy: inhibits uterine motility which, increases potential for implantation and allows uterus to contain fetus.
d. Estrogen: (194) secreted by ovary at the beginning of pregnancy, then by placental cells. Stimulates: increases uterine size and weight, develops mammary ducts, and various other things.
2. Metabolic functions
b. Nutrition: provided by plactena.
c. Excretion: from baby through the plactena to mom and out of mom.
d. Storage: iron and other products.
E. Membranes
1. Chorion: (139) develops from the trophoblast and is the outermost membrane and closest to the uterine lining.
2. Amnion: (140) small at first and fills with fluid to become the amniotic sac. Contains 1L of amniotic fluid at term.
F. Amniotic Fluid
At term approx. 800-1200 ml of fluid
Oligohydramnios < 300 ml (fetal renal abnormalities)
Hydramnios > 2000 is associated with GI and other malformations
1. Functions of Amniotic Fluid
a. "wedge" to help soften and dilate cervix during labor
b. provides physician with valuable diagnostic information when analyzed
c. fluid for fetus to swallow
d. medium for fetal movement
e. thermal regulation
2. Composition
albumin, urea, uric acid, creatinine, lecithin, sphingomyelin, bilirubin, fructose, fat, leukocytes, proteins, epithelial Cells, enzymes, and lanugo
3. Amniocentesis
A sampling of amniotic fluid by needle puncture through abdominal wall of mom into amniotic sac to obtain fluid for Dx of genetic disorders, fetal abnormalities and fetal lung maturity.
G. Yolk Sac (156): about 13-15 days gestation, angioblasts organize as blood islands in the mesoderm of the yolk sac, spaces form and become lined with angioblasts forming primitive blood vessels and endothelium. These cells give rise to primitive blood cells. All this occurs in the yolk sac.
H. Germ Layers (137): ectoderm, endoderm, and mesoderm.
I. Umbilical Cord (142): the connection between embryo and placenta. Starts with 2 veins and 2 arteries. One vein atrophies early in gestation leaving one, which carries oxygenated blood to embryo.
J. Fetal Circulation (148): purposes: (see fig 7-14)
decrease blood flow to fetal lungs
increase blood flow to head and heart
direct blood to placenta
K. Characteristics that allow the fetus to obtain sufficient 02 from maternal blood (148): shunts (ductus venosus – liver to vena cava and ductus arteriosus – lungs) to head and heart.
L. Respiratory System (148): lungs collapsed, majority of blood shunted due to constriction and shunted through ductus arteriosus to aorta.
M. Reproductive System (152): develops with urinary system. Testes in abdomen seen @ 7 weeks, 30 weeks descend.Ovaries in abdomen stay there. External genitalia are a good indicator of gestational age.