UNIT 1 (A-F) Flashcards
When does embryonic gender differentiation occur?
8 weeks gestation (reproductive organs present)
What are the types of pelvis’s and the preferred?
**Gynecoid
Android
Anthropoid
Platypelloid
What uterine muscles contract during labor? Prepare for implantation/pregnancy?
Myometrium
Endometrium
What is the ph’s of the vagina, what do the changes provide? How are the veins located? What risk does this pose?
4-5 during reproductive life (acidic prevents infection, except candida)
7.5 during infancy to puberty and menopause (kills sperm at this level)
Bypass heart and lungs, straight to brain and spine. (Infection can cause meningitis)
What are the phases of the menstrual cycle?
Menstrual phase (1-6) Proliferative phase (7-14) Ovulation phase (14) Secretory phase (15-26) Ischemic phase (27-28)
When is the menstrual phase? What occurs?
Days 1-6.
Endometrial lining sheds, and glands regenerate.
Low estrogen levels.
scant, viscous, opaque cervical mucosa.
When is the proliferative phase? What occurs in this time?
7-14
Increasing estrogen levels
Endometrial glands enlarge, tissue thickens
Blood vessels dilate
Cervical mucus stretchy, clear, thin, watery, alkaline
What phase occurs on day 14? What happens during this time?
Ovulation phase
Mature ova release (due to FSH and LH) and viable 6-24 hours. Cervical mucosa-elastic-spinnbarkeit
Body temp drops prior to ovulation and inc. 0.5-1 at ovulation.
Mittelsschmerz (mild cramps)
(Born w/ 400,000. 30,000 by puberty)
When does the secretory phase begin? What occur during this time?
15-26
Influenced by progesterone
Inc uterus vascularity
Inc myometrial gland secretion (prep for fertilized egg)
What is the last menstrual cycle phase? What days will this occur? What changes occur?
Ischemic phase (if fertilization doesn’t occur)
27-28
Corpus lutes degenerates
Estrogen/progesterone levels decrease
Blood escapes via endometrial stromal cells (menstruation begins)
What four factors encourage fertilization?
Fructose in semen provides sperm energy.
Prostaglandins in semen inc uterine muscle contractions to transport sperm.
High estrogen levels inc peristalsis in Fallop tubes and cause mucosa thinning.
Fallop tubes have cilia to move ovum and sperm.
What factors makes fertilization difficult?
Ovum fertile for only 6-24 hours
Sperm live 48-72 hours (best for 24)
200-300 million sperm ejaculation but only hundreds reach ampulla (where fertilization occurs)
Explain the cleavage - mitosis division cell stages. (3 days)
Blastomere-dividing cells (zygote rapid division as it moves along the fallopian tube via ciliated epithelium).
Morula:12-32 cells.
Blastocyst:inner mass of cells (develops into embryo/membrane)
Trophoblast:outer layer (replaces zona pellucida) develops into chorion.
When is implantation complete? How does this occur?
Day 9
Trophoblast (chorion) attaches to endometrium burrowing into uterine lining becoming chorionic villi (helps supply nutrients to fetus). Secretes early preg protein. Progesterone helps thicken endometrium and prepare for implantation.
When and what do blastocyst cells differentiate (3 different layers)?
10-14 days
Outermost is chorionic membrane w/ chorionic villi.
Inner chorion is thin amnion with amniotic fluid (except where umbilical connects)
By when is the yolk sac and amnion well developed? What is the yolk sacs job?
4 1/2 weeks
Makes primitive RBC’s (until liver able)
How much amniotic fluid is present by the 3rd trimester? Define too little or too much and those amounts. What are the amniotic fluids functions?
700-1000ml Oligohydramnios <400ml Hydramnios/polyhydramnios >2000ml Injury protection Temp control Permit growth/development Freedom of movement Prevent umbilical compression Fetal protection during labor Provides analysis fluid
From what does the umbilical cord develop? Size? What does it contain? Function?
Amnion. 2cm X 50-60cm. Attaches embryo to yolk sac, fuses with embryonic portion of placenta. Provides path form chorionic villi to embryo.
2 arteries, 1 vein surrounded by Wharton jelly (protection).
Vein provides circulatory pathway to embryo. Artery carries away waste.
If only one artery present, look for GI, Renal, or cardiac issues.
For identical twins, how does division effect number of chorionic/amnion?
Monozygotic (1 egg)
W/I 4 days:2 embryo, 2 amnion, 2 chorion.
4-8 days:2 embryo, 2 amnion, common chorion.
8-12 days: 2 embryo, 1 amnion, 1 chorion.
For fraternal twins, how are the anatomy arranged?
Dizygotic (2 eggs) 2 placentas (sometimes fuse appearing as one), 2 chorion, 2 amnions
How long does growth of placenta continue?
What are the two sides?
20 weeks and covers half of the uterus lining on Maternal side-cotyledons are the anchoring villi. If left behind during labor, causes hemorrhage.
Fetal side-chorionic villi w/ amnion.
First 3-5 months little nutrient exchange. Then thins and allows full exchange until too old to function (41 weeks).
What are the 5 placental hormones?
HCG Progesterone Estrogen HPL Immunologic
What are the functions of placenta hormone hCG?
Prevents involution of corpus luteum and abortion.
Causes CL to inc estrogen/progesterone levels.
Stims testes to produces testosterone to cause male organs to develop.
Immunologic capabilities keep placenta from rejecting placenta and embryo.
Used as basis for pregnancy test in blood at implantation (8-10 days after fertilization) and one month in urine.
What are placental functions?
Fetal respiration
Delivery of nutrients, o2, waste excretion, stores glycogen/iron
Endocrine: corpus luteum works as temp placenta until it produces enough hormones alone.
What does the placental hormone progesterone do?
Inc secretions of Fallopian tube to provide nutrition for morula. Helps with implantation. Dec contractility of uterus to dec abortions.
What does the placental hormone estrogen do?
Enlargement of uterus and breast. Inc vascularity and vasodilation in end of preg. Production inc dramatically toward end of preg.
What does the placental hormone HPL do and immunilogic functions?
HPL:stim changes in mothers metabolic processes to ensure more protein, glucose, and minerals are avail for fetus.
Immune: due to placental production of progesterone, hcg, and chorionic villi.
When is the embryonic stage? What occurs each week in this stage?
Day 15-8 weeks
- Week 2-3:blood circulation begins, tubular heart forms (3rd week)
- Week 4:brain/spinal cord formed, tubular heart beats.
- Week 8: heart complete. (Heard w/doppler) Some movement, genitals all appear similar.
When is the fetal stage? What occurs in each of these weeks?
End of 8 weeks-birth
-End of 8th week:all organs present
-15-20 weeks:sex determination, scalp hair lanugo present.
-21-27 weeks:myelination of spinal cord, fetus sucks/swallows amniotic fluid, peristaltic movement begins, lanugo
-24 weeks: respiratory movements, alveoli appear produce surfactant, gas exchange possible, skin covered in vernix.
AGE OF VIABILITY!
-28 weeks: adipose, nails, eyebrows/eyelashes, testes descend, eyelids open.
-36 weeks: lanugo disappear (protective layer).
-38-40:Lecithin-sphingomylin ratio inc indicating dec risk of resp distress during birth.
What are the chromosomal genetic d/o categories? What occurs?
Monosomic-missing a chromosome, only 45, miscarry early on.
Trisomic-extra chromosome, 47, Down’s syndrome, the lower the number the worse the condition.
Mosaicism-2genetic materials in same person, more common in sex chromosome, failure of some chromosomes to separate during fertilization. High functioning downs syn.
What are the monosomic/trisomic sex chromosome aneulpoidies d/o’s?
Mono-turner syndrome 45 chromo X (females)
Tri-klinefelter synd 47 XXY (Males)
What are other chromosomal abnormalities?
Inversion:loss or gain of chromo (causes: chemicals, smoking, drinking, drugs, radiation, viruses)*risk of leuk, ca, hemophilia.
Translocation:transfer of part/entire chromo. *risk of metal/phy disa.
Deletion:cri du chat syndrome 99%abort (missing on 5)
How are autosomal dominant and autosomal recessive different?
And the common d/o?
DOM: affected child has affected parent. No carriers. 50% chance of affected child. Huntingtons (deg of brain C#4) Polycystic kidney dz Neurofibromatosis Achondroplastic dwarfism REC:both parents must be carriers.50% carrier, 25%affected. Cystic fibrosis Sickle cell (C#9) Tay-sachs dz Most metabolic d/o (PKU) Albinism
When is genetic u/s best performed?
16-20 weeks
Must have f/u screening
What is NTT nuchal translucent test? When is it best performed?
U/s that scans clear area on back of fetal neck. Excess fluid is representative of some genetic d/o’s (downs). screens trisomy 13, 18, 21.
1st trimester 10-14 weeks.
False pos and false negs.
What is MSAFP? What is it sig for? When is it done?
Blood serum test. Elevated when neural tube defects. Low levels indicate downs.
15-18 weeks (important to know accurate dates)
High false positives.
(May check plasma at same time that helps with downs dx)
Describe the quad screen. What is indicated with inc/dec levels?
Maternal serum test. AFP:alpha fetoprotein hCG:human chorionic gonadotropin UE3:unconjugated estriol 3 dim Eric inhibin-A (hormone from placenta)
High AFP-neural tube defects (or twins)
Low AFP-downs trisomy 18
High hCG and inhibin-A, low UE-downs
What is the purpose of the maternity 21/Harmony testing?
Blood testing. Screens for trisomy 13, 18, 21.
Very effective. Can determine sex at 10 weeks.
When can an amniocentesis be performed? Why is it indicated?
For chromosomal after 15 weeks. Age over 35 Prev child w/ chromosomal abnormal Parent carrier Mother w/ x linked Parents w/inborn error of metab Parents w/ autosomal recessive Fam hx neural tube defect Pos screen tests
What are PUBS and CVS testing used for? When can these be performed?
Pub-blood for rapid dx, genetics, RH. Blood from cord. After 18 weeks.
Cvs-sim to amnio. 8-10 weeks (cervically/abdominal)-cannot R/O neural tube defects-too early.
What does the doppler flow study look for? What can occur with poor result? How is this determined?
Umbilical velocimetry (blood flow between uterus and placenta)
Uteroplacental insuff-fetal anemia.
Inc press=placental d/o
S/D ratio 2.6 by 26wks, 3 at term.
How is amniotic fluid analyzed? For what? When?
Amniocentesis: AFP early on-15-16 weeks.(Quad screen) Fetal abnormals/genetics/maturity. 3rd TRIMESTER: L/S ratio 35 weeks:PG LBC (lamellar body ct) Delta OD 450: for fetal life threat anemia. Allows for transfusion (usually from rh- mom w/o rhogam shot) 15-20ml fluid. Rhogam admined if RH-.
