OB timeline (weeks & numbers)

Your patient has spotting and bleeding and came in to check the viability of her pregnancy. Due to irregular periods shes had a previous US 9 days ago which measures a MSD of 10mm. Based on previous findings, will you see a CRL today? Heart rate?

Since the MSD grows 1.1mm a day (MSD has grown 9.9 mm) this puts the MSD to 20mm which is under the discriminatory level. (You will more than likely see a CRL) If you see a CRL and it measures >7mm you will see a heart beat

The fetal urinary bladder becomes sonographically apparent at _______ weeks? a. 10 to 12 b. 12 to 13 c. 13 to 14 d. 14 to 15

a. 10 to 12

The cranial bones ossify by ____ weeks. a. 12 b. 14 c. 16 d. 18

a. 12

With transvaginal sonography, the earliest appearance a normal intrauterine gestational sac should be seen with a serum beta hCG greater than ______ mIU/ml. a. 500 b. 1000 c. 1500 d. 2000

a. 500

Embryos w/heart rates below ______ bpm generally have a poor prognosis? a. 90 b. 100 c. 105 d. 110

a. 90

Which one of the following statements about the gestational sac is FALSE? a. Blood tests should be positive 7 - 10 hours after conception b. The earliest structure observed within the gestational sac is the yolk sac c. The embryo may be seen at 4 weeks with transvaginal ultrasound d. The placenta is seen as a thickened density along part of the margin of the gestational sac

a. Blood tests should be positive 7 - 10 hours after conception

Which one of the following statements about the embryo heart rate is FALSE? a. Early in the developmental phase, the heart rate is greater than 190 bpm b. Early in the developmental phase, the heart rate is 90 bpm c. The rate may increase to 170 bpm in the middle of the first trimester d. The rate is 120 - 140 bpm in the second & third trimester

a. Early in the developmental phase, the heart rate is greater than 190 bpm

By 9 weeks, the yolk sac should measure ____________ millimeters (mm) in diameter. a. Less than 5 b. Greater than 5 c. Less than 2 d. Greater than 2

a. Less than 5

An embryo should be seen when the MSD equals ________?

25mm

Fetal heartbeat should be seen when CRL equals ________?

7mm

The development of conjoined twins occurs when the division of the egg occurs: A) 13 days postconception B) 3 days postconception C) 8 days postconception D) 25 days postconception

A) 13 days postconception

The normal length of the umbilical cord measures ______ centimeters (cm). A) 40 to 60 B) 60 to 90 C) 30 to 50 D) 20 to 35

A) 40 to 60

Holoprosencephaly and proboscis are MOST likely to be found in a fetus with which one of the following? A) Trisomy 13 B) Trisomy 18 C) Trisomy 21 D) Turner syndrome

A) Trisomy 13

Premature labor is defined as the onset of labor before how many weeks gestation? A. 37 B. 38 C. 39 D. 40

A. 37

A short cord measures less than ______ cm. A) 25 B) 35 C) 30 D) 40

B) 35

Even with a known menstrual date, conception may occur from day ______ to day ______. A) 1; 15 B) 6; 27 C) 10; 18 D) 15; 27

B) 6; 27

Predictors of discordance growth of twins include all except which of the following? A) A difference in estimated fetal weight of greater than 20%. B) A difference in biparietal diameter of 10 mm or greater. C) A difference in abdominal circumference of 20 mm or greater. D) A difference in femur length of 5 mm or greater.

B) A difference in biparietal diameter of 10 mm or greater.

In the first trimester, the length of the umbilical cord is approximately the same size as which one of the following? A) Mean (gestational) sac diameter B) Crown-rump length C) Biparietal diameter D) Femur length

B) Crown-rump length

Advantages of chorion villus sampling (CVS) may include all EXCEPT which of the following? A) It is performed in the first trimester. B) The results are available within 48 hours. C) The results are available within 1 week. D) Early results allow more options for parents.

B) The results are available within 48 hours.

The sonographic findings of cranial anomalies, choroid plexus cysts, facial abnormalities, and rocker bottom feet may be found in which one of the following? A) Trisomy 13 B) Trisomy 18 C) Trisomy 21 D) Turner syndrome

B) Trisomy 18

Hydrops caused by fetal tachycardia most commonly demonstrates a heart rate ranging between how many beats per minute and how many beats per minute? A. 160;200 B. 200;240 C. 210;250 D. 225;250

B. 200;240

The following sonographic findings of increased nuchal thickening, shortened femurs, cardiac anomalies, and pyelectasis may be found in which one of the following? A) Trisomy 13 B) Trisomy 18 C) Trisomy 21 D) Turner syndrome

C) Trisomy 21

An AFI of 7 cm is considered: A) polyhydramnios B) oligohydramnios C) within lower limits of the normal amniotic fluid volume D) premature rupture of membranes

C) within lower limits of the normal amniotic fluid volume

Which one of the following is demonstrated if the division of one fertilized egg occurs 4 to 8 days after fertilization? A. Two chorions and two amnions B. One amnion and two chorions C. One chorion and two amnions D. One amnion and one chorion

C. One chorion and two amnions

A hypoplastic umbilical artery is defined as a three-vessel cord when the artery-to-artery differences is greater than _____. A) 30% B) 25% C) 75% D) 50%

D) 50%

The normal amniotic fluid index (AFI) should range between: A) 1;5 cm B) 5;8 cm C) 8;16 cm D) 5;22 cm

D) 5;22 cm

A long umbilical cord measures greater than _____ cm. A) 100 B) 120 C) 60 D) 80

D) 80

A large cystic hygroma, hydrops, and coarctation of the aorta may be seen in a fetus with which one of the following? A) Trisomy 13 B) Trisomy 18 C) Trisomy 21 D) Turner syndrome

D) Turner syndrome

Stuck twin syndrome is usually observed between how many weeks gestation and how many weeks gestation? A. 12;14 B. 12;24 C. 16;20 D. 16;26

D. 16;26

TRUE OR FALSE: CRL is measured between 12 - 16 weeks.

FALSE Use the earliest ultrasound with a CRL of at least 10mm (around 7 weeks)

TRUE OR FALSE: The fetal pole should be identified in a gestational sac measuring 21mm

FALSE gestational sac greater than or equal to 25mm

Your patient has 2 kids at home, has had a therapeutic abortion, and has had 2 miscarriages, what is her GPA?

G6 P2 A3

Before starting your next exam you check Netcare for your patients hCG levels. 48 hours ago they read 300 mIU/mL. What if you dont see a gestational sac today, should we worry?

NO, Since the hCG levels are around 600 mIU/mL (they double every 2 days), we may see the gestational sac but since its under the discriminatory value (2000-3000) we would not worry if we didn't

Macrosomnia is defined as birth weight of which of the following? a. above 90% for estimated gestational age b. above 3900 grams c. above 95% for estimated gestational age d. at or above 95% for estimated gestational age

a. above 90% for estimated gestational age

All of the following statements related to CRL are true except: a. measured between 12 to 16 weeks b. best measured when fetus is in an uncurled position c. optimal method of establishing fetal age d. EDC (estimated date of confinement) should be based on earliest fetal CRL on all patients who have had a first trimester ultrasound.

a. measured between 12 to 16 weeks

In early pregnancy, the gestational sac size grows at a rate of ______ mm/day? a. 0.5 b. 1 c. 2 d. 2.5

b. 1

When 2 first trimester ultrasounds are performed, the one with the crown rump length greater than ______mm is the most accurate one a. 5 b. 10 c. 12 d. 14

b. 10

The optimal gestational age for measuring the nuchal translucency is _____ weeks. a. 10 to 12 b. 11 to 13 c. 14 to 16 d. 18 to 20

b. 11 to 13

MSAFP levels increase with advancing gestational age and peak _______ weeks' gestation a. 14 - 16 b. 15 - 18 c. 18 - 20 d. 16 -20

b. 15 - 18

Diagnostic ultrasound has been in use since late in which one of the following decades? a. 1940s b. 1950s c. 1960s d. 1970s

b. 1950s

Nuchal skin fold thickness of 5 mm or less is normal up to ____ weeks' gestation. a. 18 b. 20 c. 22 d. 24

b. 20

The embryonic heart begins to beat at _____ days? a. 23 b. 35 c. 43 d. 49

b. 35

A heart beat can often be seen as early as the end of the _______ th week. a. 4 b. 5 c. 6 d. 7

b. 5

The diameter of the normal yolk sac should never exceed _____ mm. a. 4 b. 6 c. 8 d. 10

b. 6

The normal atrium of the lateral ventricle measures ____ mm. a. 4 b. 6 c. 8 d. 10

b. 6

Approximately _____% of all pregnant women in the USA are examined with sonography. a. 50 b. 65 c. 75 d. 100

b. 65

Normal physiologic midgut herniation should not be larger than ________ mm a. 5 b. 7 c. 9 d. 12

b. 7

When the CRL is greater than ______________ mm a heart beat must be seen a. 5 b. 7 c. 10 d. 12

b. 7

With transvaginal ultrasound, an abnormal pregnancy is suspected when visualizing the yolk sac fails with a minimum mean sac diameter (MSD) of _____ mm? a. 6 b. 8 c. 10 d. 12

b. 8

The fetal production of urine and the ability to swallow begin during which of the following weeks' gestation? a. 6 to 9 b. 8 to 11 c. 10 to 13 d. 9 to 15

b. 8 to 11

A fetal lip typically closes by: a. 18 weeks b. 8 weeks c. 13 weeks d. 6 weeks

b. 8 weeks

Linear acceleration of the embryonic heart rate correlates well with gestational age up to _______________ weeks. a. 8 menstrual b. 9 gestational c. 10 menstrual d. 12 conceptional

b. 9 gestational

Early in gestation, the major source of amniotic fluid is produced by which one of the following? a. Yolk sac b. Amniotic membranes c. Yolk stalk d. Chorionic villi

b. Amniotic membranes

Which of the following statements about the amniotic fluid development is true? a. The fetal kidneys begin to produce urine in the first trimester b. In the first trimester, fluid is produced by the placenta c. The fluid decreases in volume until the 34th week d. The fetus gains two thirds of its weight during the first two trimesters

b. In the first trimester, fluid is produced by the placenta

What is the equation for mean sac diameter? a. MSD = L x W x AP / 3 b. MSD = L + W + AP / 3 c. length x width x height d. length + width + height

b. MSD = L + W + AP / 3

Which one of the following statements about the amniotic fluid volume (AFV) is false? a. The amniotic fluid increases in the early second trimester by 25 milliliters (ml). b. The amniotic fluid increases in the third trimester by 50 ml. c. The amniotic fluid increases in the late second trimester by 50 ml. d. The amniotic fluid in the third trimester does not change significantly.

b. The amniotic fluid increases in the third trimester by 50 ml.

The AFI may be approximated by multiplying the largest pocket of amniotic fluid by ____________. a. Two b. Three c. Four d. Five

b. Three

IUGR is most commonly defined as a fetal birth weight ____ for a given gestational age. a. below 10% b. at or below 10% c. at or below 5% d. below the 5%

b. at or below 10%

The anechoic center of a 5 to 6 week gestation sac represents which one of the following? a. amniotic cavity b. chorionic cavity c. decidual reaction d. primary yolk sac

b. chorionic cavity

You are scanning a 10 week pregnancy with the dates verified by ultrasound. You spot a bright echo within the gestational sac. What would this echo be? a. corpus albicans b. normal amnion c. trophoblast d. dedidua basalis

b. normal amnion

A sonogram at 10 weeks' gestation demonstrates a cystic area within the posterior cranium. This appearance most likely represents which one of the following? a. abnormal mesencephalon b. normal rhombencephalon c. abnormal reombencephalon d. normal prosencephalon

b. normal rhombencephalon

The most common cause of vaginal bleeding in the 1st trimester is which one of the following? a. placenta previa b. subchorionic hemorrhage c. ectopic pregnancy d. missed abortion

b. subchorionic hemorrhage

The dates established by sonography examinations performed in the second trimester typically take precedence over the menstrual age when the discrepancy is greater than _____ days. a. 5 b. 7 c. 10 d. 15

c. 10

Nuchal translucency must be measured between ____ weeks and ______ weeks, ______ days? a. 8. 10, 6 b. 10, 12, 6 c. 11, 13, 6 d. 12, 13, 6

c. 11, 13, 6

Typically, the yolk sac resorbs and is no longer visible sonographically by ______ weeks? a. 8 b. 10 c. 12 d. 14

c. 12

In the first trimester, herniated bowel will return within the abdominal cavity by the ______ week? a. 8th b. 10th c. 12th d. 15th

c. 12th

The CRL measurement may be used up to the _____ gestational week? a. 10th b. 11th c. 12th d. 13th

c. 12th

The 2nd trimester is between _____ gestational weeks. a. 12 - 21 b. 12 -28 c. 13 - 26 d. 15 - 30

c. 13 - 26

The fusion of the chorion & amnion occurs between _____ weeks? a. 9 and 10 b. 11 and 12 c. 14 and 15 d. 20 and 21

c. 14 and 15

Corpus luteum cysts regress and are typically not seen beyond _______ weeks? a. 10 to 12 b. 12 to 14 c. 16 to 18 d. 18 to 20

c. 16 to 18

Fetal anatomy may be assessed accurately after _____ weeks gestation. a. 14 b. 16 c. 18 d. 21

c. 18

Interval fetal growth may be determined by sonographic measurements ____ weeks apart. a. 1 to 2 b. 2 to 3 c. 2 to 4 d. 4 to 6

c. 2 to 4

Amniotic fluid may appear generous during ______ weeks' gestation. a. 12 to 15 b. 15 to 20 c. 20 to 30 d. 36 to 40

c. 20 to 30

Polyhydramnios is defined as an AFV greater than _______ ml. a. 1500 b. 1750 c. 2000 d. 2250

c. 2000

Serum maternal hCG levels in a normal intrauterine pregnancy less than 7 weeks should increase by doubling every _______? a. 24 hours b. 48 hours c. 3.5 days d. 1 week

c. 3.5 days

Visualization of the distal femoral epiphysis signifies a gestational age beyond: a. 28 to 30 weeks b. 31 to 33 weeks c. 33 to 35 weeks d. all of the above

c. 33 to 35 weeks

The blastocyst typically enters the uterus ____ days after fertilization? a. 1 to 2 b. 2 to 3 c. 4 to 5 d. 7 to 9

c. 4 to 5

The yolk sac should be less than ______ mm a. 2 b. 4 c. 6 d. 8 e. 10

c. 6

Congenital anomalies of the face occur in 1 in _____ births. a. 2000 b. 1500 c. 600 d. 1200

c. 600

With normal transvaginal sonography, cardiac activity should be demonstrated when the CRL exceeds ____ mm. a. 5 b. 6 c. 7 d. 8

c. 7

The beta hCG levels plateau & subsequently decline, whereas the gestational sac continues to grow after _____ weeks? a. 3 to 5 b. 6 to 8 c. 9 to 10 d. 10 to 12

c. 9 to 10

An S/D ratio of the umbilical artery can be used to evaluate fetal well-being: a. beginning 20 wks gestation b. after 25 wks gestation c. after 30 wks gestation d. throughout pregnancy

c. after 30 wks gestation

The absence of an embryo in an intrauterine pregnancy of 7 to 8 weeks is consistent with which one of the following? a. placenta previa b. ectopic pregnancy c. anembryonic pregnancy d. multiple gestation

c. anembryonic pregnancy

Beyond 30 weeks' gestation, a renal pelvis is considered abnormal when measuring greater than ____ millimeters (mm). a. 4 b. 6 c. 8 d. 10

d. 10

Implantation into the uterine decidua is completed within ____ days after fertilization? a. 2 b. 5 c. 10 d. 12

d. 12

Cranial anatomy is routinely visualized after how many gestational weeks? a. 8 to 10 b. 9 to 11 c. 10 to 12 d. 12 to 14

d. 12 to 14

When the gestational mean sac diameter (MSD) exceeds ____ millimeters, an embryo with definite cardiac activity should be clearly seen with transvaginal scanning. a. 7 b. 10 c. 13 d. 16

d. 16

Transvaginally, an embryo w/cardiac activity should be identified when the gestational sac measures ______ mm? a. 5 to 8 b. 8 to 12 c. 10 to 15 d. 16 to 20

d. 16 to 20

In transabdominal scanning, a normal gestational sac can be consistently demonstrated when the beta hCG is ________ mega international units per milliliter (mIU/ml)? a. 500 b. 1000 c. 1500 d. 1800

d. 1800

All long bones should be measured if the difference between the femur length and all other biometric parameters is which one of the following? a. greater than 3 weeks b. greater than 4 weeks c. greater than 1 week d. 2 weeks or greater

d. 2 weeks or greater

When the BHCG is greater than ______________ mIU/ml an embryo must be seen a. 1000-2000 b. 1500-2000 c. 2000-2500 d. 2000-3000

d. 2000-3000

At what gestational week does the volume of amniotic fluid stop increasing? a. 28th b. 30th c. 32nd d. 34th

d. 34th

What percentage of the cystic hygromas is associated with chromosomal anomalies? a. 15 b. 25 c. 30 d. 50

d. 50

Normally, the fetal bladder empties at least every ______________. a. 10 minutes b. 15 minutes c. 3 hours d. 60 minutes

d. 60 minutes

Signs of polyhydramnios include all of the following sonographic demonstrations except: a. Appearance of a free-floating fetus within the amniotic cavity b. Accentuated fetal anatomy as increased amniotic fluid improves image resolution c. Amniotic fluid index (AFI) greater than 20 centimeters (cm) d. AFI greater than 15 cm

d. AFI greater than 15 cm

Using the maximum vertical depth method of assessing the AFV, a pocket __________________________. a. Less than 3 cm indicatesoligohydramnios b. Greater than 7 cm indicates polyhydramnios c. Between 1 and 7 cm is considered normal d. Between 2 and 8 cm is considered normal

d. Between 2 and 8 cm is considered normal

Which of the following is also referred to as Trisomy 21? a. Edwards syndrome b. Patau syndrome c. Meckel-Gruber syndrome d. Down syndrome

d. Down syndrome

Where is the rhombencephalon located on a 10 wk obstetric scan? a. Frontal and cephalic b. Posterolateral c. Rostral to the xygomatic bone d. Posterior midline e. Ventral midline

d. Posterior midline

Twin pregnancies have a _____ median AFI than a singleton pregnancy. a. Slightly higher b. Similar c. Significantly lower d. Slightly lower

d. Slightly lower

Which of the following is also referred to as Patau syndrome? a. Trisomy 18 b. Trisomy 21 c. Trisomy 12 d. Trisomy 13

d. Trisomy 13