Test Ordering:
(1) serum progesterone in ng/mL: with a positive pregnancy test, a serum progesterone level of >= 25 ng/mL indicates a normal intrauterine pregnancy, while a value <= 5 ng/mL indicates a nonviable fetus
(2) serum beta-HCG in mIU/mL
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Progesterone
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Boolean
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beta-HCG
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Assessment
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>= 25 ng/mL
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OR
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>= 100,000 mIU/mL
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Viable intrauterine pregnancy
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|
< 25 but > 5 ng/mL
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|
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Perform transvaginal ultrasound. If intrauterine gestational sac not seen, look for ectopic sac and measure diameter.
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<= 5 ng/mL
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OR
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abnormal rise (see below)
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Perform D & C. If chorionic villi seen, then completed abortion. If no chorionic villi seen, monitor beta-HCG at 12 hours (see below).
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Rise in serum HCG during pregnancy:
(1) normal: with intrauterine pregnancy, serum beta-HCG should rise by at least 66% over the initial level at 24 hours
(2) abnormal: an increase of serum beta-HCG by less than 66% indicates a pregnancy not developing normally, and could indicate an ectopic pregnancy
Management if no chorionic villi seen at D & C:
(1) if beta-HCG at 12 hours after D & C has decreased by at least 15%, then diagnosis consistent with completed abortion
(2) if beta-HCG at 12 hours after D & C has not decreased by at least 15%, then perform transvaginal ultrasound and look for ectopic gestational sac and measure diameter.
Management of ectopic pregnancy based on gestational sac diameter:
(1) if sac size is < 4 cm: administer methotrexate
(2) if sac size is >= 4 cm: treat surgically
