USMLE Step 2 CK-OB/GYN Exam Study Questions 2022/23
COMPLETE SOLUTION
What is Nagele's rule? - ✔✔due date = LMP + 9 months + seven days
What is developmental age? - ✔✔number of weeks and days since fertilization. typi
...
USMLE Step 2 CK-OB/GYN Exam Study Questions 2022/23
COMPLETE SOLUTION
What is Nagele's rule? - ✔✔due date = LMP + 9 months + seven days
What is developmental age? - ✔✔number of weeks and days since fertilization. typically used only in
research, as the exact date of fertilization is not commonly known
What is gestational age? - ✔✔number of wks and days measured from the first day of the LMP.
How else can gestational age be determined? - ✔✔Fundal height: at 20wks, uterus is at the umbilicus
and grows approx 1 cm/wk
Quickening, or appreciation of fetal movt: typically occurs at 17-18 wks
Fetal heart tones: can be heard at 10-12 wks by Doppler
Ultrasound: measures fetal crown-rump length (CRL) at 5-12wks and measured biparietal diameter
(BPD), femur length (FL), and abd circumference (AC) from 13 wks. U/S measurement of GA is most
reliable during the first trimester
How does renal flow change in pregnancy? - ✔✔increases 25-50%
How does glomerular filtration rate change in pregnancy? - ✔✔increases early, then plateaus
How does uterine weight change in pregnancy? - ✔✔increases from about 60-70g to about 900-1200g
How does body weight change in pregnancy? - ✔✔average 11kg (25lb) increase
What is the standard for diagnosing pregnancy? - ✔✔B-hCG
- produced by placenta; peaks at 100,000 mIU/mL by 10wks of gestation
- decreases throughout the second trimester; levels off in the third trimester
- hCG levels double approx every 48hrs during early pregnancy. This is often used to diagnose ectopic
pregnancy when doubling is abnormal
What is a quantitative B-hCG used for? - ✔✔- to diagnose and follow ectopic pregnancy
- to monitor trophoblastic disease
- to screen for fetal aneuploidy
What is a quad screen? - ✔✔1) Maternal serum alpha-fetoprotein
- produced by the fetus, crosses the placenta in small amounts and enters the maternal circulation
- Elevated: assoc w/ open neural tube defects (anencephaly, spina bifida), abd wall defects
(gastroschisis, omphalocele), multiple gestation, incorrect gestational dating, fetal death, and placental
abnormalities (e.g. placental abruption)
- Decreased: assoc w/ trisomy 21 and 18, fetal demise, and inaccurate gestational dating.
2) inhibin A
3) estriol
4) B-hCG
What quad screen results suggest Trisomy 18? - ✔✔ALL four decreased
What quad screen results suggest Trisomy 21 - ✔✔decreased AFP and estriol
Increased B-hCG and inhibin A
How does heart rate change in pregnancy? - ✔✔gradually increases 20%
How does blood pressure change in pregnancy? - ✔✔gradually decreases 10% by 34 wks, then increases
to prepregnancy values
How does stroke volume change in pregnancy? - ✔✔increases to maximum at 19wks, then plateaus
How does cardiac output change in pregnancy? - ✔✔rises rapidly by 20%, then gradually increases an
additional 10% by 28wks
How does peripheral venous distention change in pregnancy? - ✔✔progressive increase to term
How does peripheral vascular resistance change in pregnancy? - ✔✔progressive decrease to term
How does respiratory rate change in pregnancy? - ✔✔unchanged
How does tidal volume change in pregnancy? - ✔✔increases by 30-40%
How does expiratory reserve change in pregnancy? - ✔✔gradual decrease
How does vital capacity change in pregnancy? - ✔✔unchanged
How does respiratory minute volume change in pregnancy? - ✔✔increases by 40%
How does blood volume change in pregnancy? - ✔✔increases by 50% in second trimester
How does hematocrit change in pregnancy? - ✔✔decreases slightly
How does fibrinogen change in pregnancy? - ✔✔increases
How do electrolytes change in pregnancy? - ✔✔unchanged
How does sphincter tone change in pregnancy? - ✔✔decreases
How does gastric emptying time change in pregnancy? - ✔✔increases
What is the recommended amount of weight women should gain in pregnancy? - ✔✔an additional 100-
300 kcal/day; 500 kcal/day during breastfeeding
Excessive gain: >1.5kg/mo
Inadequate gain: <1 kg/mo
What are the nutritional guidelines for pregnancy? - ✔✔folic acid supplements (decrease neural tube
defects for all reproductive-age women): 0.4 mg/day
Iron: 30mg/day of elemental iron
Calcium: 1300 mg/day for women <19yo; 1000mg/day >19yo
Vitamin D: 10ug or 400IU/day
Vitamin B12: 2ug/day
What is PAPP-A? - ✔✔pregnancy-assoc plasma protein A
recommended at wks 9-14 to detect Down Syndrome and Trisomy 18 risk
combined with ultrasound-determined nuchal transparency (fluid in the fetal neck) + B-hCG
What is CVS? - ✔✔chorionic villus sampling
recommended at wks 10-12
involves transcervical or transabd aspiration of placental (chorionic villi) tissue
What are the advantages and disadvantages of CVS? - ✔✔Ads
- diagnostic accuracy comparable to that of amnio, available at 10-12wks
Disads
- carries risk of fetal loss (1-2%); cannot detect open neural tube defects
What are complications of CVS? - ✔✔limb defects have been assoc w/ CVS performed = 9wks
How often should prenatal visits occur? - ✔✔Wks 0-28: every four wks
Wks 29-35: every 2 wks
Wks 36-birth: every wk
What kind of testing should be completed at the initial prenatal visit? - ✔✔Heme: CBC, Rh factor, type
and screen
ID: UA and culture, rubella ab titer, HBsAg, RPR/VDRL, cervical gonorrhea and chlamydia, PPD, HIV, Pap
smear (to check for dysplasia)
If indicated: HbA1c, sickle cell screening
Discuss genetic screening: Tay-Sachs, CF
What kind of prenatal testing should be completed at 9-14wks? - ✔✔offer Triple Screen
- PAPP-A
- nuchal transparency
- free B-hCG +/- CVS
What kind of prenatal testing should be completed at 15-20wks? - ✔✔Offer Quad Screen
- AFP
- estriol
- B-hCG
- inhibin A
+/- amniocentesis
What kind of prenatal testing should be completed at 18-20wks? - ✔✔ultrasound for full anatomic
screen
What kind of prenatal testing should be completed at 24-28 wks? - ✔✔1hr glu challenge test for
gestational diabetes screen
What kind of prenatal testing should be completed at 28-30 wks? - ✔✔RhoGAM for Rh (-) women (after
ab screen)
What kind of prenatal testing should be completed at 32-36wks? - ✔✔GBS; repeat CBC
What kind of prenatal testing should be compeleted at 34-40wks? - ✔✔cervical chlamydia and
gonorrhea cultures, HIV, RPR in high-risk pts
What is an amniocentesis? - ✔✔recommended 15-20wks
consists of transabdominal aspiration of amniotic fluid using an ultrasound guided needle and eval of
fetal cells for genetic studies
What are the advantages and disadvantages of an amniocentesis? - ✔✔Ads
- detects ~80% of open neural tube defects, ~85% of cases of Down syndrome, and ~60% of cases of
trisomy 18
Disads
- risks: premature rupture of membranes, chorioamnionitis, and fetal-maternal hemorrhage, which can
result in fetal loss (0.5%)
When is an amniocentesis indicated? - ✔✔- women wh
[Show More]