Prenatal Diagnosis Flashcards
1
Q
what is the definition of gestational age?
A
age in days or weeks from the last menstrual period
2
Q
what is the definition of an embryo?
A
from time of fertilization to 8 weeks (GA 10 weeks)
3
Q
what is the definition of a fetus?
A
after 8 weeks to time of birth
4
Q
what is a previable infant?
A
infant delivered before 24 weeks
5
Q
term is what?
A
37-42 weeks
6
Q
post-term?
A
past 42 weeks
7
Q
what is gravidity?
A
number of times a woman has been pregnant
8
Q
what is parity? includes what?
A
number of pregnancies led to birth after 20 weeks (or >500g infant)
includes:
-term, preterm, abortions, living children
9
Q
what are the goals of prenatal care?
A
- accurate estimate of gestational age
- deliver healthy, term infant w/out impairing mom
- treat high-risk complications
- patient education
10
Q
what’s the cardiac output change in a pregnant mom?
A
cardiac output increases 30-50%
11
Q
what’s the stroke volume in a pregnant mom?
A
stroke volume increases 10-50%
12
Q
what’s the pulse change in a pregnant mom?
A
pulse increases about 15-20bpm
13
Q
is there a murmur associated pregnancy?
A
Yes, common to have systolic ejection murmur and S3 gallop
14
Q
what happens to the BP to the mom in pregnancy?
A
peripheral vascular resistance falls
fall in BP in 2nd trimester, return to normal during 3rd trimester
15
Q
what doesn’t change in the respiratory system of a mom in pregnancy?
A
respiratory rate, vital capacity, inspiratory reserve volume
16
Q
what decreases in the respiratory system of a mom in pregnancy?
A
functional residual capacity, expiratory reserve volume, total lung capacity
17
Q
what increases in the respiratory system of a mom in pregnancy?
A
inspiratory capacity and tidal volume
18
Q
what increases in the renal system of pregnant mom?
A
increased kidney size and weight, ureteral dilation, bladder becomes intra-abdominal organ
increase in tubular reabsorption of Na
increase in renin and angiotensin levels but reduced vascular sensitivity to their hypertensive effects
19
Q
what happens to the GFR, CrCl, BUN, Cr, and glucose excretion when pregnant?
A
GFR increases 50%
CrCl increases 150-200 cc/min
BUN and serum Cr decrease by 25%
increase glucose excretion
20
Q
what happens to plasma volume, RBC volume, WBC count, and platelet count when pregnant? fibrinogen?
A
Plasma volume increases by about 50%
RBC volume increases by 30%
WBC count increases
Platelet count decreases (but still WNL)
Increased fibrinogen, factor VII-X
21
Q
what is one of the MOST COMMON complaints when pregnant?
A
CONSTIPATION -> d/t decreased motility b/c of progesterone and uterus squishing bowel
22
Q
what changes occur in the cervix when pregnant? (HINT: water content/vascularity and cervical mucous secretion)
A
increased water content and vascularity
increased cervical mucous secretion
23
Q
at 20 weeks pregnant, where do you expect the uterus to be?
A
at the umbilicus
24
Q
how can you confirm pregnancy?
A
urine HcG or serum HcG = both are the same
25
when is HcG positive?
1 week after fertilization
26
at how many weeks or Hcg can Trans-vag US show gestational sac? what about fetal heart?
gestational sac = as early as 5 weeks or Hcg of 1,500-2,000
fetal heart = as early as 6 weeks or Hcg of 5,000-6,000
27
First questions for pregnant woman?
1) was this pregnancy planned?
| 2) are you planning to continue this pregnancy?
28
what is the leading cause of pregnancy-associated death? risk factors?
homicide d/t domestic violence
RF's: age < 20, black race, late or no prenatal care
29
what are 4 main signs of pregnancy? others?
Chadwick's sign, Hegar's sign, Goodell's sign, Ladin's sign
others: breast swelling/tenderness, lines nigra
30
what is Chadwick's sign?
Pregnancy sign
bluish discoloration of vagina and cervix (d/t increased water content in cervix)
31
what is Hegar's sign?
Pregnancy sign
softening of uterine consistency and ability to palpate or compress the connection b/w the cervix and the fundus
32
what is Goodell's sign?
Pregnancy sign
softening and cyanosis of cervix at or after 4 weeks
33
what is Ladin's sign/
softening of uterus after 6 weeks
34
what is the MOST COMMON pregnancy sx?
Amenorrhea
35
initial physical exam findings for pregnancy?
Vitals, thyroid, heart, lungs, breast, abdomen (Check for scars), pelvic (pap, GC/CT, bimanual), extremities
36
what vaccine should ALL pregnant women get at first initial PE?
influenza vaccine
37
what is Nagele's Rule for determining the due date (dating) of pregnancy?
subtracting 3 months from the LMP and adding 7 days
38
how do you determine the due date if pt has uncertain LMP?
US used to determine estimate date of confinement (due date)
39
when is US most accurate in determining the due date? measure how?
most accurate in 1st trimester
done by crown-rump length in the 1st half of the 1st trimester
40
when do you check CBC w/diff of pregnant pt?
1st trimester and at 28 weeks
41
what is normal to see on CBC w/diff of pregnant pt?
slightly elevated WBC, dilution anemia, thrombocytopenia
42
if pregnant pts Hct is <32% in 1st trimester, what do you start them on?
FeSO4 and Colace
43
if MCV is low in 1st trimester pregnant pt, what should you consider and what should you get?
consider thalassemia if MCV is low
get iron studies first, if not deficient get Hgb electrophoresis
44
at what level of platelets should you be concerned about in pregnant pt? beware of?
< 100 -> thrombocytopenia
BEWARE OF HELLP SYNDROME, PRE-ECLAMPSIA
45
what are the 1st trimester labs to get?
- CBC w/diff
- Blood type and screen
- RPR/VDRL
- Rubella antibody screen
- Hep B surface antigen
- VZV titer
- Gonorrhea and Chlamydia cultures
- PPD
- Pap smear
- UA
- HIV test
46
if mom is Rh negative, what med does she need and when?
RhoGAM at 28 weeks or any time she has vaginal/uterine bleeding
47
if antibody screen for Rh is positive, who do you consult?
perinatologist
48
what can Rh antibodies do to fetal RBCs? Fatal?
destroy fetal RBCs and cause hemolytic anemia -> fatal to fetus
49
what is RPR/VDRL? testing for?
rapid plasma regain/venereal disease research lab
testing for antibodies to syphillis
50
pregnancy is a risk for what false positive?
false positive RPR/VDRL -> need to check FTA-ABS
51
if reactive/positive for RPR/VDRL, what do you check and what are you looking for? when is it a true positive?
check FTA-ABS (Fluorescent Treponemal Antibody - Absorption test)
Looking for presence of antibodies to Treponema pallidum bacteria (the bacteria that causes syphilis)
-If presence of antibodies, then is true positive
52
consult who if true positive for syphilis?
consult perinatologist
-baby can get infected if mom not treated
53
risk of what if mom is positive for syphillis?
miscarriage, stillbirth, neonatal death, or baby with severe neurological problems
54
when is Rubella vaccine given to pregnant woman?
after delivery (if non-immune)!!! b/c it is a live vaccine
55
HBsAg detects Hep B when?
detects Hep B 1-12 weeks post exposure
56
HBsAb means what?
recovery and immunity
57
HBeAg?
```
acute infection (may or may not be present in chronic infection)
-higher titer = great infectivity
```
58
acute infection of Hep B diagnosed by what antibody? detectable when? declines when?
IgM HBcAb
| -detectable at clinical onset, declines w/in 6 months
59
chronic infection of Hep B diagnosed by what antibody?
IgG HBcAb
60
if mom is infected with Hep B, who do you notify?
Peds!
61
if mom is positive for Gonorhea/Chlamydia, who do you treat? when do you do test of cure?
If positive, treat pt and partner, promote abstinence during treatment
do test of cure 4 weeks after tx
62
if PPD is positive in mom in 1st trimester, what do you do?
wait and do CXR in 3rd trimester
63
what testing should be offered to all 1st trimester women?
HIV testing
64
what screening should be offered at pre-conceptual or new OB visit, especially if white?
Cystic Fibrosis Carrier Screening
65
what is advanced maternal age (AMA)?
35 y/o or greater at time of delivery
66
what screening is offered all pregnant women, but esp to AMA pregnant women?
maternal serum screening
-blood test that looks at fetal chromosomes (MS-AFP, Quad screen, Sequential Screen, NIPT testing)
also offer genetic counseling w/possible diagnostic test (chorionic villus sampling or amniocentesis)
67
what is 2nd trimester diagnostics?
MSAFP, Quad screen, US (18-20 weeks)
68
when is MS-AFP done? what does it mean when elevated? decreased?
16-18 weeks
Elevated: increased risk of NT defects
Decreased: increased risk of aneuploidies including down Syndrome
69
what is the Quad screen? what does it check for? when is it done? what if positive?
MSAFP, HCG, estriol, inhibin-A (checks for trisomy 21, trisomy 18, NTD)
Done b/w 15-18 weeks (can go up to 20)
If positive, refer for genetic counseling, high resolution US, +/- aminocentesis
70
everyone in 2nd trimester gets what?
US - 18-20 weeks
71
what does US look for in 2nd trimester?
Fetal survey, amniotic fluid volume, placental location, gestational age
72
what is Part 1 of sequential screening in 2nd trimester?
Blood tests for serum levels of PAPP-A and free B-hCG (11-13 weeks)
US for nuchal translucency (11-13 weeks)
detects 70% of down Syndrome, 80% of trisomy 18
73
what is Part 2 of sequential screening in 2nd trimester?
Blood tests for serum levels of MS-AFP, estriol, B-hCG, and inhibin (15-18 weeks)
Detects 91% of down Syndrome, 90% of trisomy 18, and 80% of NTD
74
what is the new testing for trisomy's in maternal blood? what trisomy's does it test for?
CFFDNA analysis (cell-free fetal DNA analysis)
tests for fetal trisomy's 21, 18, 13 in maternal blood
75
what are the ACOG recommendations for use of CFFDNA analysis?
maternal age 35 y/o or older at delivery
fetal US findings indicating increased risk of aneuploidy
hx of prior pregnancy w/ trisomy
positive test result for aneuploidy, including 1st trimester, sequential, or quadruple screen
parental balanced robertsonian translocation w/increased risk of fetal trisomy 13 or trisomy 21
76
if pregnant woman has 1st trimester bleeding, what do you do?
US
77
US can be used to determine anatomy of baby at what weeks?
18-20 weeks
78
do US when fundal height is what?
any time fundal heigh is >3cm discrepant from GA
79
why is US done at or after 37 weeks?
to confirm presentation
80
reasons to do US?
At initial visit to measure CRL (crown-rump length) if uncertain LMP
First trimester bleeding
Anatomy survey b/w 18-20 weeks
Any time fundal height is >3cm discrepant from GA
Confirm presentation at or after 37 weeks
81
when is amniocentesis done and what is obtained?
b/w 15-20 weeks to obtain fetal karyotype
82
complications of amniocentesis?
- Transient vaginal spitting
- Amniotic fluid leakage
- Preterm labor
- Chorioamnionitis
83
what does ACOG recommend about doing an early amniocentesis (<15 weeks)?
DON'T DO EARLY AMINOCENTESIS (<15 weeks) b/c of higher risk of pregnancy loss and complications compared with traditional amniocentesis
84
what is Chorionic Villus Sampling? when is it done?
test to obtain fetal karyotype b/w 10-13 weeks (99% detection rate)
Catheter placed into intrauterine cavity and small amount of chorionic villi aspirated from placenta
85
complications of Chorionic Villus Sampling?
- Pre-term labor
- PROM
- Previable delivery
- Fetal injury
86
procedure-related loss rates for Chorionic Villus Sampling, the same for amniocentesis?
Yes, similar
87
what is cordocentesis?
percutaneous umbilical blood sampling (PUBS) - puncture umbilical vein w/ US guidance
get karyotype of fetal blood in 24-48 hrs
88
when is cordocentesis done?
Rarely needed but may be useful to further evaluate chromosomal mosaicism discovered after CVS or amniocentesis is performed
89
what are 3rd trimester diagnostics?
CBC, gestational DM screening , RPR/VDRL, CXR if PPD+, Group B strep culture (36 weeks)
if high risk, repeat Gonorrhea and Chlamydia cultures, HSV screening
90
when do you do CXR if pregnant woman's PPD is positive in 1st trimester?
in 3rd trimester
91
when do you get group B strep culture in pregnancy? how is it done?
36 weeks
Culture from lower vagina and anus (swab must go through sphincter)
92
what is assessed at routine prenatal visits?
- BP, weight
- Urine dipstick (protein and glucose)
- Fundal height, estimated fetal weight, fetal position
- Auscultation with doppler of the fetal heart tones
93
frequency of OB/GYN visits when pregnant?
Less than 28 weeks: every 4 weeks
28-36 weeks: every 2 weeks
>36 weeks: every week
94
do you give Zofran in pregnancy?
NO!!! give a different antiemetic
95
common problems associated with pregnancy?
constipation, hemorrhoids, GERD, Pica, urinary frequency (may be normal or UTI), carpal tunnel syndrome
96
who gets prenatal vitamins and when are they most effective?
EVERYONE GETS PRENATAL VITAMINS
800mcg folic acid - most effective when given 2 months prior and during 1st month
97
what should pregnant women avoid?
excessive fat soluble vitamins (D, A, K, E)
98
limit caffeine to what when pregnant?
limit to 500mg/day
99
consider nutritional referral in pregnancy when?
- Inadequate weight gain
- PICA
- Eating disorder
100
how much Ca is needed per day when pregnant?
1200mg
101
what is average weight gain in pregnancy?
25-35 pounds
102
if BMI >30 when pregnant, how much weight can they NOT gain? if BMI < 20, how much weight can they gain?
BMI > 30 - shouldn't gain >15lbs
BMI < 20 - gain up to 40 lbs
103
how do you tell pregnant pt to prevent listeriosis, toxoplasmosis, CMV, varicella, parvo B19?
- Handwashing
- Gloves for changing cat litter or gardening
- Wash produce and cutting boards
- Cook or freeze meats
- No raw eggs or unpasteurized dairy
104
limit radiation exposure to how many episodes when pregnant?
5 episodes
105
what are safe medications in pregnancy?
- PNV (prenatal vitamins)
- Tylenol
- Benadryl
- Sudafed (if no HTN)
- Tums
- Iron Sulfate
- Colace
106
what abx do you use for UTIs in pregnancy? can you use Bactrim?
Macrobid (nitrofurantoin)
can use Bactrim except in 3rd trimester
107
what meds can you use for BV or yeast infection in 1st trimester? after 1st trimester?
in 1st trimester: metrogel, monistat
after 1st trimester: flatly, diflucan
108
what SSRI should pregnant women avoid?
Paxil
109
what med is used to treat HSV in pregnancy?
Acyclovir
110
can pregnant women exercise? HR should be at what? what should they avoid?
YES!!!! - continue exercising at usual activity level
-want to keep HR at 140 or below
Avoid over-heating (heat is a teratogen)
111
avoid what position after 20 weeks when pregnant? why?
avoid supine position after 20 weeks b/c uterus will press on vena cava
112
2nd trimester counseling?
- Birthing classes
- Preterm labor risks after viability
- Breastfeeding
- RhoGAM at 28 weeks if Rh negative
113
3rd trimester counseling?
- Analgesia/anesthesia in labor
- Operative vaginal delivery or C-section
- Fetal kick counts
- Labor and Delivery Tour (things to bring to hospital - (i.e. car seat)
- Circumcision if boy
GBS (group B strep) -> if positive, then need abx before you deliver
114
how long does a woman need to heal from C-section before getting pregnant again?
1 year
115
if pt has had prior C-section, what must be documented? discuss what?
uterine scar (if possible)
discuss risk/benefits of vaginal birth after C-section trial vs. repeat C-section
risks to bladder and bowel
116
what is the goal of antepartum fetal surveillance?
to prevent fetal death
117
what techniques are used for antepartum fetal surveillance?
Fetal movement assessment
Non-stress test (NST)
Contraction stress test (CST)
Fetal Biophysical Profile (BPP)
Amniotic Fluid Index (AFI)
118
what is the indication for fetal movement assessment? technique? tips?
Indication: maternal perception of decreased or absent fetal movement
Technique: mother counts number of "kicks" during a specified amount of time
Tips: have mom eat or drink something, and sit or lay still
119
what is the Non-Stress Test (NST)?
Measurement of fetal heart rate with movement
| -fetal HR will accelerate with fetal movement if not acidotic or neurologically depressed infant
120
what is reactive (normal) NST?
2 or more fetal HR accelerations w/in a 20-min period
121
what is non-reactive NST?
insufficient fetal HR accelerations over a 40-min period
122
what is the contraction stress test (CST)?
Looking for presence or absence of late fetal heart rate decelerations in response to uterine contractions
123
what are late decels of fetal HR?
decels that reach their nadir (lowest point) after the peak of the contractions and usually persist beyond the end of the contraction
124
what may variable decels of fetal HR mean?
cord compression (think oligohydramnios)
125
what are the components of fetal biophysical profile (BPP)?
NST, fetal breathing movements, fetal movement, fetal tone, AFI (amniotic fluid index)
126
scoring of BPP?
- Normal: 8 or 10
- Equivocal: 6
- Abnormal: 4 or less
127
what warrants further evaluation regardless of BPP score?
oligohydramnios
128
what is the Amniotic Fluid Index (AFI)? tells you what?
Summation of the largest cord-free and baby-free vertical pockets in each of the 4 quadrants of an equally divided uterus
tells you if have oligohydramnios or polyhydramnios
129
what is oligohydramnios? is it bad? what does it require?
No US measured pocket of fluid >2cm or AFI of 5cm or less (not enough amniotic fluid)
***BAD - think anomalies or placental dysfunction
Requires close maternal/fetal surveillance or delivery
130
what is polyhydramnios? can it be normal? what can it cause?
too much amniotic fluid
| -can be normal, can cause PROM or malpresentation
131
when do you do antepartum fetal surveillance?
b/w 32-34 weeks
repeat weekly or bi-weekly until delivery
132
when is postpartum visit to OB/GYN for vaginal delivery? what do you assess?
6 weeks for vaginal delivery
Assess:
- Lochia, voiding, bowel movements, breastfeeding, depression, contraception
- Most women will bleed somewhere b/w 4-6 weeks
133
when is postpartum visit to OB/GYN for C-section delivery? when is incision checked?
2 and 6 weeks for C-section delivery
incision checked at 2 weeks
