Module 6 : First Trimester Abnormal - Extrauterine Pregnancy

Question 1

M mode determines ?

Answer 1

• only definitive way to determine abnormality/viability

Question 2

Mean Sac Diameter (MSD)

Answer 2

• gestational sac is the first thing we see on us
• used when embryo NOT identified
• ensure you see double decidual sign
• used from 4 - 7 or 8 weeks
• length + width + height / 3

Question 3

comparing MSD to Embryo

Answer 3

• used for early diagnosis of OLIGOHYDRAMNIOS (less amniotic fluid/not enough amniotic fluid)
• big red flag for abnormal pregnancy
• from 5.5 - 9 weeks if MSD(mm) - CRL(mm) = less than 5mm
  + oligohrydramnios suspected
• EFW still calculates MSD on all IVF pregnancies but only use CRL for dating of the pregnancy

Question 4

first trimester ultrasound tests

Answer 4

• MSD
• CRL
• nuchal lucency

Question 5

gestational sac sizes on EV

Answer 5

MSD 8mm = yolk sac seen

MSD 16mm = embyo seen

Question 6

gestational sac sizes on transabdominal

Answer 6

MSD 20mm = yolk sac seen

MSD 25mm = embryo seen

Question 7

gestational sac average growth

Answer 7

• 1.1mm/day

- up until 8 weeks

Question 8

Crown Rump Length (CRL)

Answer 8

• used between 6 - 13 weeks
• MOST ACCURATE MEASUREMENT TO PREDICT GESTATIONAL AGE +/- 3 DAYS
• measure from tip of head to end of rump
• do not include yolk sac
• in a neutral position

Question 9

ectopic pregnancy - definition

Answer 9

• pregnancy that occurs outside the uterine cavity

Question 10

ectopic - Classical Clinical Triad

Answer 10

• pain
• bleeding
• adnexal mass
• 45% demonstrate these symptoms

Question 11

other ectopic symptoms

Answer 11

• Amenorrhea
• adnexal tenderness
• cervical tenderness

Question 12

timing of ectopic pregnancy

Answer 12

• usually present themselves between 5 - 8 weeks
  + to small to cause any pain before this time
  + also when they start to rupture because of lack of blood supply

Question 13

factors increasing risk of ectopic

Answer 13

• tubal surgery
• pregnancy with an intrauterine contraceptive device
• pelvic inflammatory disease PID or STD
• previous ectopic
• endometriosis (endometrium travels to fallopians)
• previous appendicitis
• Khrons disease

Question 14

common ectopic sites

Answer 14

• Fallopian tube (95%)
• cervix
• interstitial segment of tube
• ovary
• peritoneal cavity

Question 15

highest risk ectopic locations

Answer 15

• cervix and cornua (interstitial) areas are the most dangerous
• high risk of hemorrhage because there are very vascular areas with little or no thickened endometrium for the embyo to burrow into
• also no coagulation takes place to bleeding out may occur

Question 16

sonographic features of ectopic

Answer 16

• adnexal mass
• free fluid
  + in pouch of Douglas even up to kidneys in Morrisons pouch
• absence of and IUG (intrauterine gestational sac) or presents with pseudo sac
• may see a viable ectopic pregnancy instead of adnexal mass

Question 17

viable ectopic pregnancy

Answer 17

• gestational sac with an embryo with a heart beat seen outside the uterus
• this is 100% accurate diagnosis of an ectopic
• may also indicate the at pregnancy has not yet ruptured

Question 18

Menstrual history

Answer 18

• DONT trust info given by patient in case of ectopic
• knowing when first pregnancy test was positive is helpful
  + can assume patient was atlas 4 weeks pregnancy at this time
• good question to ask every OB patient

Question 19

b hCG

Answer 19

• common to have lower than normal level of beta hCG or still be in normal range
• b hCG should double every 2 days in a normal pregnancy but should not with an ectopic pregnancy

Question 20

DDx (differential diagnosis) using blood work

Answer 20

- early gestation 
   \+ 5 weeks 
   \+ b hCG should increase
- Spontaneous abortion 
   \+ b hCG should decrease
- PID
   \+ pelvic inflammatory disease
   \+ b hCG negative - not pregnant

Question 21

heterotopic pregnancy

Answer 21

• intrauterine pregnancy with a twin ectopic pregnancy
• 1/7000 incidence
• incidence has increase with ART (assisted reproductive technology/IVF)
  + 1/100

Question 22

negative ultrasound results

Answer 22

• does not rule out ectopic
• may be to small to recognize with sonography
• MUST FOLLOW UP
  + EV if not done already
  + repeat bhCG in 2 days
  + repeat scan in 1 week

Question 23

interstitial line sign

Answer 23

• echogenic line extending from the endometrial canal up to the centre of the interstitial sac or hemorrhagic mass
• used to help diagnose interstitial ectopic pregnancy

Question 24

how much myometrium must be surrounding gestational sac

Answer 24

• MUST HAVE MINIMUM OF 5mm OF MYOMETRIUM SURROUNDING IT

- if not interstitial ectopic

Question 25

cervical ectopic

Answer 25

• very low in uterus

- if moves with pressure from EV then its a spontaneous abortion if doesnt move then ectopic pregnancy

Question 26

treatment for ectopic - surgery

Answer 26

• resection of diseased tube

- ow patient has an increased risk of repeat of ectopic

Question 27

treatment for ectopic - medically

Answer 27

• with methotrexate
  + cell growth inhibitor
  + used in cancer patients to arrest growth of cancer
• injected IV, IM or directly into ectopic site
• or taken orally

Question 28

treatment of acute ectopic - laparoscopy

Answer 28

• surgical removal with laparoscope
• when medical treatment has failed
• hemodynamically unstable
  + internal bleeding

Question 29

treatment of acute ectopic - laparotomy

Answer 29

- may be required if ectopic is 
    \+ abdominal 
    \+ cornual
    \+ interstitial
    \+ cervical
    \+ patient is severely hemodynamically unstable or in shock

Question 30

conservative management

Answer 30

• some early ectopics can resolve on their own
  + decreasing hCG
  + absent gestational sac
• medical treatment
  + methotrexate = single or multiple doses
• monitoring hCG