Obstetrics Part 1 Flashcards
Define Chadwick Sign
Bluish discoloration of vagina and cervix seen in pregnancy
Define Goodell Sign
Softening and cyanosis of cervix at or after 4 weeks gestation
Define Ladin Sign
Softening of the uterus after 6 weeks gestation
Other than the three named signs of pregnancy, describe other signs and symptoms of pregnancy.
breast swelling/tenderness, linea nigra develops from umbilicus to pubis, telangiectasias (spider veins), palmar erythema, amenorrhea, N/V, quickening (fetal movement).
Describe cardiovascular changes seen in pregnancy.
30-35% inc in CO max at 20-24 weeks s/p inc in SV.
SVR and arterial BP inc s/p inc in progesterone
SBP (5-10) & DBP (10-15) dec that nadirs at 24 weeks
Inc in RBC mass and volume by 20-30%
Dec Hct s/p 50% inc in plasma volume
Hypercoagulability with no change in bleeding or clotting times
WBC inc to 20 million during labor
Describe gastrointestinal changes seen in pregnancy.
Nausea s/p inc estrogen, progesterone, and Hcg resolves by 16 weeks.
Reflux s/p delayed emptying and dec LE sphincter tone
Describe renal changes seen in pregnancy.
Inc pyelonephritis s/p inc in kidney size and dilated ureters.
GFR inc by 50%
RAAS inc with inc aldosterone but no inc in Na s/p inc in GFR.
Describe pulmonary changes seen in pregnancy.
Vt inc by 30-40%
TLC dec by 5% s/p pressure on diaphragm.
Describe endocrine changes seen in pregnancy.
Hyperestrogenic state
hCG x2 48 hours into pregnancy and peaks at 10-12 weeks then declines to steady state by week 15
Placenta produces hCG to maintain corpus luteum
CL produces progesterone to maintain endometrium
Prolactin increases
T3/T4 inc with slight early dec in TSH but overall patient remains euthyroid
Describe metabolic changes seen in pregnancy.
Caloric req inc by 300 during pregnancy
Caloric req inc by 500 during breast feeding
Patient should gain 20 - 30 pounds
Inc req for protein, iron, folate, and Ca
T/F: Pregnant patients see an increase incidence of carpal tunnel syndrome.
True –> compression on median nerve
Define melasma.
Brown or blue-gray patches (like freckles) on face during pregnancy
When should a patient with irregular menstrual cycles or unknown LMP be urine tested for pregnancy?
14 days after last intercourse to minimize possibility of false negative.
Why is a serum pregnancy test rarely used?
It is the most sensitive test but it is more expensive and results are not immediately available. A repeat urine test may substitute for serum test.
Define Naegle’s rule for determining due date.
LMP - 3 months + 7 days
Define gravida, parity, and TPAL.
G = # total pregnancies P = # of deliveries TPAL = term, preterm, abortion, and live RE: P
Define the visit schedule for prenatal care.
First visit usually occurs 6-10 weeks gestation (6-8 weeks after LMP). Pt seen every 4 weeks until 32 weeks, every 2 weeks until 36 weeks, then weekly.
What should be included when obtaining an obstetric history of prior pregnancies from a currently pregnant patient?
Date, outcome (spontaneous/therapeutic abortion, ectopic, term, mode of delivery, time in labor, birth weight, any complications).
When is fetal movement expected to begin?
18-20 weeks in primigravida and 14-18 weeks in multigravida.
When should fundal height first be checked?
20 weeks - should be level of umbilicus
When should the clinician start assessing for cervical dilation?
36 weeks
What are the most accurate methods of estimating due date?
Most accurate = crown-rump length (best in 1st trimester). Transvaginal US better than abdominal US.
State milestones to note when assessing fetal development with sonogram?
Fetal yolk sac visible ~ 5 weeks then degrades by weeks 10-12
Fetal cardiac activity by week 6
2nd/3rd trimester rely on biometric markers –> biparietal diameter and head circumference.
List blood tests indicated during 1st trimester.
CBC, Hct, blood type, ab screen, RPR (syphilis), rubella ab, Hep B surface antigen, UA and culture, varicella ab, PPD.
Describe nuchal translucency screening.
Performed at 10-13 weeks for trisomy, 13, 18, 21, and Turner Syndrome. Measures thickness of fluid build-up at back of fetus’ neck. If wide measurement then amniocentesis or chorionic villus sampling done.
List three common tests performed in the second trimester of pregnancy.
Maternal Serum Alpha Feto-Protein (MSAFP) to test for neural tube defects and Downs
US at 18-20 weeks
Amniocentesis when prenatal Dx needed/desired
Differentiate tripple testing from quad testing of MSAFP.
3 = B-hCG, estriol, and MSAFP 4 = B-hCG, estriol, MSAFP, ansd inhibin A
What second semester serum testing results indicate trisomy 21 risk? Neural tube defect risk?
T-21: inc inhibin A and dec unconjugated estriol, and dec AFP
NTD: inc AFP
What are the indications to perform an amniocentesis at 15-18 weeks gestation?
Adv maternal age, family Hx or previous child with chromosomal abnormality, abnormal serum screening test or US, prior loss of 2 pregnancies.
What is done during weekly exam visits after 36 weeks to decrease the risk of the need to induce labor?
Stripping and sweeping of membranes during cervix exam.
What tests are commonly performed during the third trimester
PO GLC challenge
Group B Strep
Antiviral prophylaxis at 36 weeks if latent HSV
Gonorrhea/Chlamydia vag culture repeated if high risk
Describe the procedure for a glucose tolerance test.
Fasting GLC challenge then obtain BGL 1 hour later. If > 130, then do fasting 100g challenge and obtain BGL at 1, 2, and 3 hours. Diagnosis requires more than 1 value out of range.
Describe parameters for monitoring fetal heart rate.
Non-stress test (NST) baseline HR should be 120-160. Normal is to see 2 accels 15 bpm above baseline for 15 sec. Persistent late decels defined as HR dec of 15 for more than 15 sec or delayed return to baseline.
What is the purpose of a biophysical profile (BPP) and what are the parameters tested?
Measures health of the fetus during pregnancy. Parameters tested = NST, amniotic fluid level, gross fetal movements, fetal tone, fetal breathing. Each parameter scores up to 2 points –> risk of asphyxia rises as score rises.
Describe how the measured height of the uterine fundus correlates to gestation.
pubic symphysis = 12 weeks
between symphysis and umbilicus = 14-16 weeks
umbilicus = 20 weeks
from umbilicus to xiphoid = 2 cm per week
just below xiphoid = 36 - 38 weeks
slight descend below xiphoid = 38 weeks to term
What is the frequency of multiple gestation?
1 in 80 births
Differentiate between monozygotic and dizygotic twins.
Mono: aka identical (same genetic material) –> fertilization of single egg that splits into 2 –> always same sex.
Di: aka fraternal –> fertilization of two separate eggs in same pregnancy