Definitions for the strength of evidence (Class I-III) and strength of recommendations (Level A-C) are repeated at the end of the Major Recommendations field.
Interpretation of Serum Human Chorionic Gonadotropin (hCG) Levels
- Is transvaginal ultrasound useful in detecting intrauterine pregnancy when the serum hCG level is less than 1,000 mlU/mL?
Level A recommendations. None specified.
Level B recommendations. None specified.
Level C recommendations. Consider transvaginal ultrasound because it may detect intrauterine pregnancy when the serum hCG level is below 1,000 mIU/mL.
- Is transvaginal ultrasound useful in detecting ectopic pregnancy when the serum hCG level is less than 1,000 mlU/mL?
Level A recommendations. None specified.
Level B recommendations. None specified.
Level C recommendations. Consider transvaginal ultrasound because it may detect ectopic pregnancy when the serum hCG level is below 1,000 mIU/mL.
- What is the role of serial quantitative hCG determinations in either diagnosing or excluding ectopic pregnancy?
Level A recommendations. None specified.
Level B recommendations. Obtain a repeat serum hCG determination at least 2 days after the initial presentation because it is useful in characterizing the risk of ectopic pregnancy and the probability of a viable intrauterine pregnancy.
Level C recommendations. None specified.
- Above what serum hCG level is the absence of intrauterine pregnancy by transvaginal ultrasound presumptive evidence of ectopic pregnancy?
Level A recommendations. None specified.
Level B recommendations. Arrange follow-up for patients with a nondiagnostic transvaginal ultrasound and a serum hCG level above 2,000 mIU/mL because they have an increased likelihood of ectopic pregnancy.
Level C recommendations. None specified.
Methotrexate in Ectopic Pregnancy
- What is the frequency of treatment failure in methotrexate therapy for ectopic pregnancy and its implication for emergency department (ED) management?
Level A recommendations. None specified.
Level B recommendations. None specified.
Level C recommendations. Because the symptoms associated with gastrointestinal side effects of methotrexate therapy may mimic an acute ectopic rupture, rule out ectopic rupture resulting from treatment failure before attributing gastrointestinal symptoms to methotrexate toxicity. Treatment failure with single dose methotrexate for ectopic pregnancy can occur in up to 36% of patients.
Rh Seroconversion and Indications for anti-D Immunoglobulin
- Is the administration of anti-D immunoglobulin indicated among Rh-negative women during the first trimester of pregnancy with threatened abortion, complete abortion, ectopic pregnancy, or minor abdominal trauma?
Threatened or Complete Abortion or Ectopic Pregnancy
Level A recommendations. None specified.
Level B recommendations. Administer 50 micrograms of anti-D immunoglobulin to Rh-negative women in all cases of documented first trimester loss of established pregnancy.
Level C recommendations. None specified.
Minor Abdominal Trauma
Level A recommendations. None specified.
Level B recommendations. None specified.
Level C recommendations. Consider administration of anti-D immunoglobulin in cases of minor trauma in Rh-negative patients.
Definitions:
Strength of Evidence
Strength of evidence Class I: Interventional studies including clinical trials, observational studies including prospective cohort studies, aggregate studies including meta-analyses of randomized clinical trials only.
Strength of evidence Class II: Observational studies including retrospective cohort studies, case-controlled studies, aggregate studies including other meta-analyses.
Strength of evidence Class III: Descriptive cross-sectional studies; observational reports including case series and case reports; consensus studies including published panel consensus by acknowledged groups of experts.
Strength of Recommendations
Level A recommendations. Generally accepted principles for patient management that reflect a high degree of clinical certainty (i.e., based on "strength of evidence Class I" or overwhelming evidence from "strength of evidence Class II" studies that directly address all the issues.)
Level B recommendations. Recommendations for patient management that may identify a particular strategy or range of management strategies that reflect moderate clinical certainty (i.e., based on "strength of evidence Class II" studies that directly address the issue, decision analysis that directly addresses the issue, or strong consensus of "strength of evidence Class III" studies).
Level C recommendations. Other strategies for patient management based on preliminary, inconclusive, or conflicting evidence, or, in the absence of any published literature, based on panel consensus.
