EM OB 10: Ectopic Pregnancy

Question 1

most important consideration among obstetric-related conditions in the first 20 weeks of pregnancy until it can be either confirmed or excluded with conviction

Answer 1

ectopic pregnancy

Question 2

The sensitivity of quantitative serum testing for the diagnosis of pregnancy is virtually 100% when an assay is capable of detecting:

Answer 2

≥5 mIU/mL of B-hCG

Question 3

a leading cause of maternal death in the first trimester of pregnancy

Answer 3

ruptured ectopic pregnancy

Death results from maternal exsanguination after tubal rupture.

Question 4

maternal age ______ is a major risk factor for ectopic pregnancy

Answer 4

35-44y
(age-related change in tubal function)

Question 5

TRUE or FALSE
Missed menses are always reported in ectopic pregnancy

Answer 5

FALSE
No missed menses are reported in 15% of ectopic pregnancy cases.

Question 6

remarks on pregnancy in a patient with prior tubal surgery for sterilization

Answer 6

Pregnancy in a patient with prior tubal surgery for sterilization is assumed to be an ectopic pregnancy until proven otherwise.

Question 7

Most common symptom of ectopic pregnancy

Answer 7

abdominal pain or discomfort

Question 8

remarks on B-hCG in pathologic pregnancies

Answer 8

Absolute levels of B-hCG are lower and doubling times longer in ectopic pregnancy and other abnormal pregnancies

hCG levels that fail to increase by 53% or more in 2 days are suggestive but not diagnostic of ectopic pregnancy or an abnoramal IUP.

Question 9

most pathologic pregnancies have progesterone levels of:

Answer 9

</=10 ng/mL

with progesterone ≤5 ng/mL, nearly 100% of pregnancies will be pathologic

but still, the role of serum progesterone assays in excluding or definitively diagnosing ectopic pregnancy is currently unclear

Question 10

Progesterone levels _____ have 97% sensitivity for viable IUP.

Answer 10

> 25 ng/mL

Question 11

what is a viable IUP

Answer 11

an embryo with cardiac activity seen within the uterine cavity is referred to as viable IUP

Question 12

Transvaginal UTZ timeline in visualization of early sonographic signs of pregnancy

Answer 12

4.5 weeks: gestational sac
5.5 weeks: yolk sac
6.0 weeks: fetal pole

Visualization by transabdominal scanning can be done approx 1 week later

Question 13

this sonographic finding confers a risk of ectopic pregnancy near 100%

Answer 13

the combination of an echogenic adnexal mass with free fluid in the setting of an empty uterus confers a risk of ectopic pregnancy near 100% (97%)

whereas a large amount of free fluid alone [already] has an 86% risk

Question 14

TRUE or FALSE
The finding of hepatorenal fluid has ~100% risk of ectopic pregnancy in high-risk patietns

Answer 14

TRUE

(Table 98-4)

Question 15

Describe discriminatory zone

Answer 15

The discriminatory zone is the level of B-hCG at which findings of an IUP are expected on US.

A B-hCG level higher than the discriminatory zone and an empty uterus on US suggest an ectopic pregnancy

Question 16

discriminatory zone for transvaginal scanning

Answer 16

B-hCG of 1500 mIU/mL

Question 17

discriminatory zone for transabdominal scanning

Answer 17

B-hCG of 6000 mIU/mL

Question 18

Most frequently used surgical approach for ectopic pregnancy

Answer 18

laparoscopic salphingostomy

Question 19

most frequently used medical approach for ectopic pregnancy

Answer 19

systemic methotrexate
- folic acid antagonist that inhibits dihydrofolate reductase, causing depletion of cofactors needed for DNA and RNA synthesis
- IM is the most commonly used approach (50 mg/m2 single dose or multiople doses)

Question 20

Absolute contraindications to methotrexate adminsitration

Answer 20

IUP
Evidence of immunodeficiency
Moderate to severe anemia, leukopenia, or thrombocytopenia

sensitivity to methotrexate
active pulmonary disease
active PUD

Clinically important hepatic or renal dysfunction
Breast feeding
Hemodynamic instability

Question 21

Relative contraindications to methotrexate administration

Answer 21

Embryonic cardiac activity detected by transvaginal US
hCG >5000 mIU/mL
ectopic pregnancy >4 cm in size as imaged by transvaginal US

refusal to accept blood transfusion
inability to reliably return for follow up

Question 22

Most common side effect with methotrexate

Answer 22

abdominal pain (up to 75%)

Lower abdominal pain lasting up to 12 hours is common 3 to 7 days after methotrexate treatment and is though to be secondary to methotrexate-induced tubal abortion or tubal distention due to hematoma formation (“separation pain”)

The pain is usually self-lmitied and may respond to NSAIDs

Question 23

Other remarks with abdominal pain after methotrexate treatment

Answer 23

a clinical dilemma - still could be rupturing persistent ectopic pregnancy.

It is suggested to test for CBC and do abdominopelvic US to rule out tubal rupture and hemoperitoneium.

Patient may need admission for observation.

Question 24

RhoGAM in ectopic pregnancy

Answer 24

Recommendations: 50 mcg of RhoGAM for Rh-negative women with ectopic pregnancy when diagnosed prior to 12 weeks of gestation due to small volume of red cells in the fetoplacental circulation, although administration of a full dose of 300 mcg is acceptable as well