 |
Early first trimester normal ultrasound survey MCQ & Quiz |
Early first trimester normal ultrasound survey Question of
Good Try! good effort।
You out of You have corrected the question!
You have scored points ।
A. Yolk sac
B. Gestational sac
C. Embryonic pole
D. Double decidual sac sign
Correct Answer: A. Yolk sac
Explanation:While the gestational sac is the earliest structure seen on ultrasound, it is not specific to an intrauterine pregnancy. The yolk sac is the first structure definitively located within the gestational sac, confirming an intrauterine pregnancy.
MCQ 2: At what gestational age is a transvaginal ultrasound expected to detect fetal cardiac activity?
A. 4 weeks
B. 5 weeks
C. 6 weeks
D. 8 weeks
Correct Answer: C. 6 weeks
Explanation:By 6 weeks of gestation, transvaginal ultrasound typically detects fetal cardiac activity, which appears as a flickering motion within the embryo.
MCQ 3: Which structure is used to estimate gestational age in early pregnancy before 14 weeks?
A. BPD (Biparietal diameter)
B. HC (Head circumference)
C. CRL (Crown-rump length)
D. FL (Femur length)
Correct Answer: C. CRL (Crown-rump length)
Explanation:CRL is the most accurate measurement for estimating gestational age in the first trimester, especially between 6 and 13 weeks of gestation.
MCQ 4: A gestational sac should be visible by transvaginal ultrasound at a beta-hCG level of approximately:
A. 500 mIU/mL
B. 1000 mIU/mL
C. 1500 mIU/mL
D. 3000 mIU/mL
Correct Answer: C. 1500 mIU/mL
Explanation:The discriminatory zone for visualizing an intrauterine gestational sac by transvaginal ultrasound is generally a serum β-hCG ≥1500–2000 mIU/mL.
MCQ 5: What is the normal growth rate of the embryo during early first trimester?
A. 0.5 mm/day
B. 1 mm/day
C. 2 mm/day
D. 3 mm/day
Correct Answer: B. 1 mm/day
Explanation:The embryo typically grows at a rate of approximately 1 mm per day in the early first trimester, which helps in estimating gestational age over serial scans.
MCQ 6: What structure is seen within the gestational sac around 5.5 weeks?
A. Embryo
B. Amnion
C. Yolk sac
D. Limb buds
Correct Answer: C. Yolk sac
Explanation:The yolk sac is typically visible at 5.5 weeks and is a key structure for confirming intrauterine pregnancy.
MCQ 7: What does the double decidual sac sign represent?
A. Ectopic pregnancy
B. Twin pregnancy
C. Normal intrauterine implantation
D. Gestational trophoblastic disease
Correct Answer: C. Normal intrauterine implantation
Explanation: The double decidual sac sign is an early indicator of a normal intrauterine pregnancy.
MCQ 8: When does the amniotic sac typically become visible on ultrasound?
A. 4 weeks
B. 5 weeks
C. 6 weeks
D. 7 weeks
Correct Answer: C. 6 weeks
Explanation: The amniotic sac becomes distinguishable at approximately 6 weeks gestation.
MCQ 9: Which structure gives nutrition to the developing embryo before the placenta forms?
A. Chorion
B. Yolk sac
C. Decidua
D. Umbilical cord
Correct Answer: B. Yolk sac
Explanation: The yolk sac provides early nutritional support until the placenta takes over.
MCQ 10: Which of the following indicates a non-viable pregnancy in the first trimester?
A. CRL 4 mm with no cardiac activity
B. Gestational sac of 10 mm with yolk sac
C. Gestational sac of 5 mm without yolk sac
D. CRL 6 mm with visible heartbeat
Correct Answer: A. CRL 4 mm with no cardiac activity
Explanation: Absence of cardiac activity when CRL ≥ 7 mm is considered diagnostic of pregnancy failure.
MCQ 11: What is the most common site of ectopic pregnancy?
A. Cervical
B. Ovarian
C. Interstitial
D. Ampullary
Correct Answer: D. Ampullary
Explanation: The ampullary portion of the fallopian tube is the most common location for ectopic pregnancies.
MCQ 12: When does the fetal pole typically become visible on transvaginal ultrasound?
A. 4 weeks
B. 5 weeks
C. 6 weeks
D. 8 weeks
Correct Answer: C. 6 weeks
Explanation: The fetal pole appears around 6 weeks and is accompanied by cardiac activity.
MCQ 13: What is the threshold mean sac diameter (MSD) above which an embryo should be visible?
A. 10 mm
B. 15 mm
C. 20 mm
D. 25 mm
Correct Answer: D. 25 mm
Explanation: If the MSD is ≥25 mm with no embryo, a failed pregnancy is diagnosed.
MCQ 14: What is the earliest sonographic feature suggesting pregnancy?
A. Fetal heart motion
B. Yolk sac
C. Gestational sac
D. Fetal pole
Correct Answer: C. Gestational sac
Explanation: The gestational sac is the first visible sign of pregnancy, usually seen around 4.5 to 5 weeks.
MCQ 15: What ultrasound feature is diagnostic of chorionicity in twin pregnancy during the first trimester?
A. Number of yolk sacs
B. Heart rate differences
C. Lambda or twin-peak sign
D. Gestational age discrepancy
Correct Answer: C. Lambda or twin-peak sign
Explanation: The twin-peak (lambda) sign is suggestive of dichorionic twins.
MCQ 16: Which sonographic feature helps differentiate a true gestational sac from a pseudogestational sac?
A. Round shape
B. Central location in uterus
C. Presence of a yolk sac
D. Anechoic center
Correct Answer: C. Presence of a yolk sac
Explanation: A pseudogestational sac lacks a yolk sac and is usually centrally located, while a true gestational sac is eccentrically located and contains a yolk sac.
MCQ 17: When is the chorionic bump seen, and what does it indicate?
A. Normal yolk sac development
B. Threatened miscarriage
C. Subchorionic hematoma
D. Non-specific finding with increased miscarriage risk
Correct Answer: D. Non-specific finding with increased miscarriage risk
Explanation: A chorionic bump is an irregular projection into the gestational sac and is associated with an increased risk of pregnancy loss.
MCQ 18: What is the normal fetal heart rate (FHR) range at 6 weeks?
A. 80–100 bpm
B. 100–115 bpm
C. 90–110 bpm
D. 120–160 bpm
Correct Answer: B. 100–115 bpm
Explanation: At 6 weeks gestation, the normal fetal heart rate ranges between 100–115 bpm and increases to 120–160 bpm by 8–10 weeks.
MCQ 19: The "intradecidual sign" is an early sign of what?
A. Tubal pregnancy
B. Intrauterine pregnancy
C. Gestational trophoblastic disease
D. Fetal demise
Correct Answer: B. Intrauterine pregnancy
Explanation: The intradecidual sign represents an early gestational sac implanted within the endometrium and supports diagnosis of intrauterine pregnancy.
MCQ 20: By what gestational age should the yolk sac typically disappear?
A. 8 weeks
B. 10 weeks
C. 12 weeks
D. 14 weeks
Correct Answer: C. 12 weeks
Explanation: The yolk sac regresses and is no longer visible on ultrasound by the end of the first trimester, around 12 weeks.
MCQ 21: A normal yolk sac diameter should be less than:
A. 4 mm
B. 5 mmv C. 6 mm
D. 7 mm
Correct Answer: B. 5 mm
Explanation: A yolk sac larger than 5–6 mm is considered abnormal and may be associated with poor pregnancy outcomes.
CQ 22: A gestational sac should grow approximately how much per day in early pregnancy?
A. 0.5 mm/day
B. 1 mm/day
C. 1.5 mm/day
D. 2 mm/day
Correct Answer: B. 1 mm/day
Explanation: The gestational sac typically enlarges about 1 mm/day during the early first trimester.
MCQ 23: Which of the following is a normal finding at 7 weeks?
A. MSD 6 mm with no yolk sac
B. CRL 6 mm with no heartbeat
C. CRL 10 mm with cardiac activity
D. FHR 85 bpm
Correct Answer: C. CRL 10 mm with cardiac activity
Explanation: A CRL of 10 mm with visible cardiac activity is a normal and reassuring sign at 7 weeks gestation.
MCQ 24: What does the presence of subchorionic hemorrhage suggest in first trimester?
A. Molar pregnancy
B. Normal finding
C. Risk of miscarriage
D. Ectopic pregnancy
Correct Answer: C. Risk of miscarriage
Explanation: A subchorionic hemorrhage is associated with increased risk of first trimester loss, especially if large.
MCQ 25: What is the earliest structure seen within the gestational sac?
A. Embryo
B. Yolk sac
C. Amnion
D. Fetal pole
Correct Answer: B. Yolk sac
Explanation: The yolk sac appears before the embryo and is the first visible structure confirming intrauterine pregnancy.
MCQ 26: A normal amnion should always be seen by what CRL size?
A. 5 mm
B. 7 mm
C. 10 mm
D. 12 mm
Correct Answer: C. 10 mm
Explanation: The amnion should be seen surrounding the embryo when CRL is ≥10 mm.
MCQ 27: Which measurement is not useful in the first trimester dating scan?
A. CRL
B. MSD
C. HC
D. Yolk sac diameter
Correct Answer: C. HC
Explanation: Head circumference (HC) is used after 13–14 weeks; CRL and MSD are used earlier.
MCQ 28: What is the earliest gestational age where limb buds may be visible?
A. 5 weeks
B. 6 weeks
C. 7 weeks
D. 8 weeks
Correct Answer: C. 7 weeks
Explanation: Limb buds can be visualized starting at 7 weeks, typically as small protrusions from the embryo.
MCQ 29: What is the “double bleb” sign?
A. Two yolk sacs in twin pregnancy
B. Visualization of yolk sac and amnion before embryo appears
C. Twin gestational sacs
D. Sign of failed pregnancy
Correct Answer: B. Visualization of yolk sac and amnion before embryo appears
Explanation: The double bleb sign is a normal first trimester finding of the amnion and yolk sac adjacent to each other.
MCQ 30: The CRL measurement should be taken in which ultrasound view?
A. Oblique plane with curved fetus
B. Transverse plane
C. True midsagittal plane with neutral position
D. Sagittal view with flexed neck
Correct Answer: C. True midsagittal plane with neutral position
Explanation: CRL must be measured in a straightened, midsagittal view for accurate gestational dating.
No comments:
Post a Comment