1: Prenatal care Flashcards
Bluish discoloration of vagina and cervix
Chadwick sign
Softening and cyanosis of the cervix at or after 4 wk
Goodell sign
Softening of the uterus after 6 wk
Ladin sign
B-hCG timeline
will rise to a peak of 100,000 mIU/mL by 10 weeks of gestation, decrease throughout the second trimester, and then level off at approximately 20,000 to 30,000 mIU/mL in the third trimester.
A viable pregnancy can be confirmed by ultrasound, which may show the gestational sac as early as ?? on a transvaginal ultrasound or at a β-hCG of ??
5 weeks
1,500 to 2,000 mIU/mL
baby considered an embryo until ?? weeks gestation, then fetus
8 weeks
trimesters
The first trimester lasts until 12 weeks but is also defined as up to 14 weeks’ GA, the second trimester lasts from 12 to 14 until 24 to 28 weeks’ GA, and the third trimester lasts from 24 to 28 weeks until delivery.
parity (P)
the number of pregnancies that led to a birth at or beyond 20 weeks’ GA or of an infant weighing more than 500 g.
a woman who has given birth to one set of preterm twins, one term infant, and had two miscarriages would be a
G4 P1-1-2-3
fetal movement or “quickening” occurs between
16 and 20 weeks
ways to estimate GA: auscultation of FHR at how many weeks?
20 weeks by nonelectronic fetoscopy or at 10 weeks by Doppler ultrasound
how does cardiac output change during pregnancy?
increases by 30-50%
- most during 1st trimester
- increase in SV then maintained by increased in HR
how does SVR and BP change during pregnancy?
SVR decreases–>BP decreases (5-10/10-15 mmHg decrease)
- due to elevated progesterone–>smooth muscle relaxation
- returns to prepreg BP at 24 weeks
how do lung volumes change during pregnancy?
30% to 40% in tidal volume (VT)–>same RR so 30-40% increase in minute ventilation–>increase in alveolar (PAO2) and arterial (PaO2) PO2 levels and a decrease in PACO2 and PaCO2 levels.
total lung capacity (TLC) is decreased by 5% due to the elevation of the diaphragm
how does PaCO2 change in pregnancy?
decreases to about 30 mmHg (from 40)
-leads to an increased CO2 gradient between mother and fetus which facilitates oxygen delivery to the fetus and carbon dioxide removal from the fetus
Dyspnea of pregnancy occurs in 60% to 70% of patients; possibly secondary to ??
decreased PaCO2 levels, increased VT, or decreased TLC.
morning sickness, due to ??
N/V typically resolves by ??
elevation in estrogen, progesterone, and hCG; possibly hypoglycemia
14-16 wks gestation
Hyperemesis gravidarum
severe form of morning sickness associated with weight loss (≥5% of prepregnancy weight) and ketosis.
how do kidneys change in pregnancy?
GFR?
RAAS?
increase in size, ureters dilate–>increase rates of pyelo
GFR increases by 50% early–>BUN/Cr decrease by 25%
-increase in RAAS–>increased aldo–>increase Na+ reabsorption (but plasma Na+ levels don’t increase due to increased GFR)
anemia of pregnancy
plasma volume increases by 50%, the RBC volume increases by only 20% to 30%, which leads to a decrease in the hematocrit, or dilutional anemia
WBC in preg?
platelets?
WBCs increase to 6-16 million/mL
platelets decrease (100-150 million/mL)(dilute/destruction)
pregnancy is a hyper coagulable state due to ?
elevations in the levels of fibrinogen and factors VII–X
actual clotting and bleeding times do not change, but increase in thromb/emb events
Fetal well-being has been correlated with maternal serum ? levels
estrogen;
low estrogen levels being associated with conditions such as fetal death and anencephaly.
(preg is hyperestrogenic state; mostly produced in placenta, some ovaries)
the alpha subunit of hCG is identical to alpha subunit of
LH, FSH, TSH
beta subunits are different
Levels of hCG double approximately every 48 hours during early pregnancy, reaching a peak at approximately ?? weeks, and thereafter declining to reach a steady state after week ?
10 to 12 weeks (up to 3 months)
week 15
hCG produced by ?
the placenta: acts to maintain the corpus luteum in early pregnancy.
progesterone produced by ?
corpus luteum, which maintains the endometrium. Eventually, the placenta takes over progesterone production and the corpus luteum degrades into the corpus albicans.
progesterone causes ??
relaxation of smooth muscle, which has multiple effects on the GI, CV, GU systems
-increases throughout preg
Human placental lactogen (hPL) is produced in the placenta
and does what ?
a constant nutrient supply to the fetus
- induces lipolysis with a concomitant increase in circulating FFAs
- insulin antagonist (diabetogenic effect, so baby gets sugar) increased levels of insulin and protein synthesis.
levels of prolactin increase or decrease during pregnancy?
increase
decrease after delivery but later increase in response to suckling
thyroid hormone changes in preg
overall, euthyroid but..
estrogen stimulates thyroid binding globulin (TBG), leading to an elevation in total T3 and T4, but free remains relatively constant
(also, hCG stimulates thyroid–>increase T3/4, decrease TSH early)
hyper pigmentation of face in pregnancy:
melasma or chloasma
due to increase in melanocyte-stimulating hormones and the steroid hormones
caloric increases during pregnancy and breastfeeding
caloric requirement is increased by 300 kcal/day during pregnancy and by 500 kcal/day when breastfeeding
(from 2000-2500 kcal/day)
Most patients should gain between ?? during pregnancy.
20 and 30 lb
Overweight women are advised to gain less, between 15 and 25 lb; underweight women are advised to gain more, 28 to 40 lb.
protein requirement in preg increases to ?
from 60 to 70 or 75 g/day
Recommended calcium intake
1.5 g/day (increased)
Folate requirements
0.4 to 0.8 mg/day
preggos should take iron if HCT falls, because may develop iron deficiency anemia due to
the increased demand on hematopoiesis both by the mother and the fetus.
initial prenatal visit should happen ?
early in the first trimester, between 6 and 10 weeks
The panel of tests in the first trimester includes ??
a CBC (HCT), blood type, antibody screen, RPR or VDRL screen, rubella antibody screen, hepatitis B surface antigen, G/C, Chlamydia culture, urinalysis and culture, PPD, Pap smear (unless 6 mos ago), VZV titer in patients with no history of exposure, HIV offered Early screening for aneuploidy (NT plus serum markers)
second trimester screening
MSAFP/triple or quad screen
U/S
amniocenteisis for women interested in prenatal diagnosis
third trimester screening
HCT, RPR/VDRL, GLT, GBS
at 27-29 weeks
if mom has SLE, test for ?
AntiRho, antiLa antibodies (can cause fetal complete heart block)
check ? at each visit
BP, weight, urine dipstick, measurement of the uterus, and auscultation of the FH
If the fundal height is progressively decreasing or is 3 cm less than GA, next step?
an ultrasound is done to more accurately assess fetal growth
serum levels of pregnancy-associated plasma protein A (PAPP-A) and free β-hCG is offered when?
between 11 and 13 weeks of gestation to all women.
Screening for maternal serum alpha fetoprotein (MSAFP) is usually performed when?
elevations/decreased levels indicate what?
between 15 and 18 weeks
elevation: neural tube defects
decrease is seen in some aneuploidies, including Down syndrome.
triple screen
MS-aFP, B-hCG, estriol
quad screen
triple + inhibin A
patients who are Rh negative should receive RhoGAM when?
at 28 weeks
GLT (glucose loading test)
50g oral glucose, check 1 hour. if >=140 mg/dL, order glucose tolerance test (GTT)
start iron supplement at these HCT/Hgb levels
hematocrit below 32% to 33% (hemoglobin
GDM dx if 2+ GTT levels are > than
fasting glucose, 95 mg/dL; 1 hour, 180 mg/dL; 2 hour, 155 mg/dL; or 3 hour, 140 mg/dL
Braxton Hicks contractions
Occasional irregular contractions that do not lead to cervical change
In the third trimester, ultrasound can be used to monitor high-risk pregnancies by obtaining what??
biophysical profiles (BPP), fetal growth, and fetal Doppler studies
BPP
looks at five categories and gives a score of either 0 or 2 for each: amniotic fluid volume, fetal tone, fetal activity, fetal breathing movements, and the nonstress test (NST), which is a test of the FHR. A BPP of 8 to 10 or better is reassuring.
A decrease, absence, or reversal of diastolic flow in the umbilical artery is progressively more worrisome for ??
placental insufficiency and resultant fetal compromise.
Formal antenatal testing
NST, the oxytocin challenge test (OCT)/contraction stress test, and the BPP.
NST is considered formally reactive (a reassuring sign) if there are ??
two accelerations of the FHR in 20 minutes that are at least 15 beats above the baseline heart rate and last for at least 15 seconds.
indications for Percutaneous umbilical blood sampling (PUBS)
for fetal hematocrit, particularly in the setting of Rh isoimmunization, other causes of fetal anemia, and hydrops, fetal transfusion, karyotype analysis, and assessment of fetal platelet count in alloimmune thrombocytopenia.
fetal lung maturity tests
L/S ratio, phosphatidylglycerol (PG), saturated phosphatidyl choline (SPC), the presence of lamellar body count, and surfactant to albumin ratio (S/A).
a reassuring contraction stress test (CST)
2 accelerations of FHR in 20 minutes that are at least 15 beats above baseline and last for at least 15 seconds
