Patients presenting in early pregnancy with symptoms of bleeding and / or pain require evaluation for ectopic pregnancy with US and / or serial hCGs, as well as exam. A referral for formal diagnostic ultrasound and / or emergency attention may be indicated.
- A patient with a positive pregnancy test and no visible pregnancy on ultrasound is said to have a Pregnancy of Unknown Location (PUL). There is a PUL Algorithm in Chapter 8 to assist in management decisions.
- Rate of hCG rise with either an ectopic pregnancy or an EPL is usually slower than expected for a viable intrauterine pregnancy.
- The minimum rate of decline expected for EPL depends on the initial hCG at presentation, but it ranges from 35-50% at 2 days (Butts 2013).
- Rate of hCG decline with ectopic is usually slower than that expected for EPL.
- Among women diagnosed with ectopic pregnancies:
- The majority had serial hCGs outside the normal range for either a viable intrauterine pregnancy (i.e. level rose < 35-53% in 2 days) or a resolving EPL (i.e. level fell <35-50% in 2 days).
- Almost a third of women had a rise or fall of hCG that was within the limits of a potential viable IUP or completed EPL.
- Therefore, use caution when following patients with symptomatic early pregnancy.
- A “normal” rise or fall in levels is not sufficient to exclude ectopic – but should be used in conjunction with other clinical data including exam, ultrasound or diagnostic aspiration.
- See Chapter 8 for more on the diagnosis of ectopic and management of EPL.
Change in the hCG Level in Intrauterine Pregnancy,
Ectopic Pregnancy, and Spontaneous Abortion
(Note: Studies from ED not abortion care setting;
An increase or decrease in the serial hCG level in a woman with an ectopic pregnancy is outside the range expected for that of a woman with a growing IUP or a EPL 71% of the time. However, the increase in the hCG level in a woman with an ectopic pregnancy can mimic that of a growing IUP, and the decrease in the hCG level can mimic that of an EPL. (Barnhart 2009)