Toni - Week 1 - Exam 1 Flashcards
What are the 4 functions of amniotic fluid?
Protection, Temperature Control, Fetal Growth, and Movement
T/F: Amniotic fluid volume is constantly changing
TRUE
How does the mother help create amniotic fluid?
Amniotic fluid is derived in part from maternal blood moving across the amnion
How does the fetus add and remove fluid volume?
Adds to amniotic fluid via urine
removes amniotic fluid by swallowing
How much does amniotic fluid increase at term?
Volume increases weekly to a LITER at term
What is oligohydramnios?
Too little fluid - could result from fetal kidney problems
What is polyhydramnios?
Too much fluid - could result from GI tract problems
What is the chorion?
the outer sac next to uterine wall
what is the amnion?
the INNER sac next to fetus. Thin & translucent, but high in tensile strength. originated from the blastocyte
What type of jelly is a characteristic of the umbilical cord and what is its function?
It is Wharton’s Jelly and it’s a thick substance that protects the vessels
How many vessels does the umbilical cord have?
3 vessels - 2 arteries and 1 vein (AVA)
- 2 arteries carry DE-OXYGENATED blood from fetus to placenta
- 1 vein carries OXYGENATED blood to the fetus
What is the average length of the cord at term?
22 inches
When the umbilical cord is cut, can the mother /fetus feel pain?
No, it lacks sensory neurons. Good to reassure fathers/partners that this will not hurt.
Where does the placenta develop and what size is it at term?
Placenta develops at the site of embryonic attachment; it’s 1/6 the size of newborn - placenta develops the size of the newborn.
What are the 4 functions of the placenta?
fetal gas exchange, nutrition, excretion, and hormone regulation
What is the placenta composed of?
maternal and fetal tissues
The layers of fetal tissues form a placental barrier, what is the purpose of this barrier?
- Materials only exchanged via diffusion
- Prevents contact between fetal and maternal blood
What are the two different surfaces of the placenta?
- maternal surface (red/uneven) attaches to uterine wall
- outer fetal surface (gray/shiny) contains umbilical vessels and cord
What is the most crucial stage of development?
the embryonic stage
What is the “all or nothing” period?
Period between ovulation and implantation
Not yet sustained by mother; sustained by corpus luteum
No teratogens effect
Will die or live with no consequence
How much blood needs to go to the liver and lungs of a developing fetus?
Just enough to nourish the tissues
What are the 3 fetal shunts?
Foramen Ovale, Ductus Venosus, and Ductus Arteriosus
What is the Foramen Ovale?
A flap in the wall between the right and left atrium of the heart that allows a large percentage of oxygenated blood to go out into the body (blood goes from RA to LA and out into the body)
- will functionally close at birth with the change in pressure gradient that will occur with normal circulation
What is the Ductus Arteriosus?
A tiny, little shunt that connects the pulmonary artery and the aorta - some that is unnecessary in the lungs/pulmonary artery carries over to the aorta.
- will functionally close at birth d/t change in pressure gradient
What is the Ductus Venosus?
A special blood vessel that connects the umbilical vein to the inferior vena cava to allow blood to bypass the liver.
- Shunts a portion of that blood flow directly to the right atrium of the ♥ (allows blood to bypass the liver)
- Closes when umbilical cord is clamped
What is the duration of a pregnancy?
10 lunar months. 9 calendar months. 3 trimesters (3 month periods). 40 weeks. 280 days.
how is the due date computed?
It is computed from the 1st day of the last menstrual period (LMP).
when does actual conception occur?
It typically occurs closer to 2 weeks after the LMP
What are the 3 ways of estimating date of delivery?
Nagele’s Rule, Measuring fundal height, and ultrasonography
What is Nagele’s Rule?
Subtract 3 months (or add 9 months) to LMP then add one day
How is the fundal height measured?
Measure from top of pubic symphysis to fundus in centimeters - from 20 wks on, the height = the gestational week of pregnancy. example: 20 weeks = 20 cm.
T/F: ultrasound is used to confirm due date or to find a more accurate due date
TRUE
What hormone do pregnancy tests measure?
Human chorionic gonadotropin (hCG) - can be detected after implantation - approx. one week after conception.
T/F: urine and serum pregnancy tests aren’t equally accurate.
FALSE they are EQUALLY accurate - urine 95% and serum 99%
Can false positives occur? What can cause them?
Yes. False + can occur if blood/protein is in urine or d/t certain drugs like tranquilizers, anticonvulsants, and hypnotics
What are presumptive signs of pregnancy and list some examples.
they are subjective signs and symptoms that woman reports; may or may not be associated with pregnancy
- amenorrhea, nausea, fatigue, urinary frequency, breast changes, and quickening (fetal movement)
What are probable signs of pregnancy? List some examples.
they are objective signs of pregnancy noted by an examiner; may or may not be associated with pregnancy
- hegar’s sign (softening lower uterine segment)
- chadwick’s sign (bluish color of vaginal mucosa)
- goodell’s sign (softening of cervix “good & soft”)
- Braxton Hick’s contractions begin 2nd trimester
- pregnancy test
- abdominal enlargement
- ballottement (palpating technique to detect floating fetus - taps on cervix to feel fetus bounce back)
What are positive signs of pregnancy?
noted by an examiner; can only be caused by pregnancy
- see baby: ultrasound
- hear baby: auscultate fetal heart
- feel baby: palpate fetal movement
What are 8 basic physiologic changes during pregnancy??
- vaginal secretions ↑; candidiasis (yeast infection) is common
- breasts ↑ in size, sensitivity, and pigment
- colostrum (yellow creamy substance) by 3rd trimester - “normal”
- ↑ incidence periodontal disease → higher risk for preterm babies
- chest circumference, air intake, and RR ↑
- congestion/nasal stuffiness - “juicy” - ↑ vascularity - don’t take decongestives; just drink water
- Marked fatigue “sleep when toddler sleeps”
how can you prevent candidiasis?
by wearing cotton underwear and by rubbing corn starch externally
How much does blood volume increase by the 30th week?
by 50%
What cardiovascular characteristics increase??
Cardiac output and pulse
What cardiovascular characteristics decrease?
vascular resistance (vasodilation) and diastolic BP in the 2nd semester
What is postural hypotension?
when a pregnant woman gets up too quickly from sitting or playing on the floor with children – light headed and dizzy
what is supine hypotensive (vena cava) syndrome?
low blood pressure when laying on back due to fetus laying on vena cava and restricting blood flow – causes light headed, dizzy, possibly faint.
What is pregnancy induced hypercoagulability?
↑ in clotting factor - body adapts in order to prevent postpartum hemorrhage
***increase risk of blood clots → postpartum
what does pelvic vein compression cause?
↓ blood flow to legs, causing venous stasis → edema, varicosities, hemorrhoids, cramps
What is physiologic anemia of pregnancy? What is considered WNL?
volume ↑ and RBC aren’t ↑ as fast as serum.
• hematocrit >/= 35 and hemoglobin >/= 10 considered to be WNL
how can women prevent clots?
exercise, elastic compression stockings, drink lots of water, avoid crossing legs, feet higher than ♥, and avoid tight clothing.