pregnancy Flashcards
progesterone levels throughout pregnancy
increases until close to term -> used to maintain pregnancy
describe relationship between estrogen and progesterone
estrogen rise as progesterone drops
describe plasma volume changes during pregnancy
increases steadily and proportional to fetus weight in 3rd trimester
due to increased aldosterone released
what is the purpose of increased plasma vol in pregnancy
- maintains BP
- dilutes peripheral whole blood
describe action of RAAS during pregnancy
activated to increase plasma vol
describe analyte changes during pregnancy
- decreased
- protein catabolism decreases
what is the purpose of upregulation of hormones and steroids in pregnancy
causes peripheral dilation to increase cardiac output
GFR during pregnancy
increases dur to increased plasma vol
increased demand for oxygen impact
increased arterial pO2
decreased arterial pCO2
endocrine impacts of pregnancy
increased TBG and T3/T4
increased HCG (acts in place of TSH)
increased ACTH, cortisol and free cortisol
describe hCG assessment
- early pregnancy detection
- doubles every day until 8th week
- decreases until 16 weeks
where is hCG found to test
urine and blood
how does trisomny 21 (downs) impact hCG
hCG levels 2x higher than expected
composition of hCG
4 subunits (2 alpha and 2 beta)
list multiple molecules of hCG
- pituitary hCG
- free beta subunit
- fetal hCG
- hyperglycosylated hCG
true or false
before placenta developed, primary hCG is hyperglycosylated
true
what form of hCG is detect in pregnancy tests
hyperglycosylated hCG
what can cause a false positive serum immunoassay of hCG
- heterophilic Ab
- RA factor
- IgA deficiency
- chronic renal failure
- end stage renal disease
describe where AFP is made
by embryonic yolk sac first then parenchymal cells in fetal liver
AFP binds what hormone
estradiol (primary estrogen)
what can elevated levels of maternal AFP indicate
- neural tube defects (mainly)
- anencephaly
define anencephaly
undeveloped brain brain and incomplete skull
define omphalocele
abdominal wall defect (intestines outside)
what can decreased maternal AFP (MS-AFP) indicate
- downs syndrome
- risk of trisomy 18
how is MS AFP measured
multiples of median (MoM)
mothers AFP/median of referance range
how is MS-AFP treated when it is higher than expected
amniotic fluid testing
- blood interferes
what is the MoM value indicative for spina bifida
7
what is the MoM value indicative of anencephaly
20
what analyte is used to screen for trisomy 21 and 18
unconjugated estriol, made in placenta
trisomy 21
downs syndrome
trisomy 18
edwards syndrome
do not live past 8 wks of gestation
inhibin A
increased in trisomy 21 during second trimester
inhibites FSH
what is included in a triple screen
AFP, hCG, eE3
what does a quad screen include
AFP, hCG, uE3 and inhibin A
what is the purpose of triple and quad screening
screening and risk estimate - not diagnostic
describe acetylcholinesterase
cholinergic enzyme in neuromuscular junctions in muscle and nerves
- diagnostic for anencephaly, spina bifida and abdominal wall defects
Pregnancy Associated Plasma Protein A (PAPP-A)
large glycoprotein produced in placenta
1st trimester screening
low concentrations seen w/ trisomy 21 (downs), 18 (edwards), 13 (pateu) and Turners
what is a low concentration of PAPP-A associated with
trisomy 13
trisomy 18
trisomy 21
turner syndrome
progesterone
establishment and maintenance of healthy pregnancy
- measured in multiple miscarriage patients
describe complications of gestational diabetes
- macrosomic (big baby)
- low blood sugar and breathing difficulties after birth
- CNS malformations
fetal fibronectin
- mucosal lining of uterus and amniotic fluid
- positive result indicates labor
neural tube defects
- one of the most common birth defects
- neural tube does not close completely
myelomeningocele
spina bifida
fusion not complete along the spinal cord
isoimmunization
fetal hemolytic disorder
pre-exlampsi
hypertension, edema and prteinuria in third trimester - delivery to cure
hyperemesis gravidarum
morning sickness - 70% of pregnancies
ectopic pregnancy
trophoblasts attach to fallopian tube instead of uterine lining
