- High sensitivity urine pregnancy test (HSPT):
- Widely available, inexpensive urine test available over the counter or in clinics.
- Simple, accurate qualitative test detecting hCG at concentrations of 20-25 mIU/mL.
- Usually positive by cycle day 32-35 (95% of pregnancies).
- May remain positive for up to 4 or more weeks following an uncomplicated abortion.
- May be used after 4 weeks to monitor for completion of a medication abortion.
- Serum quantitative hCG test:
- Available in clinics only with an order from a healthcare provider
- Detects serum levels of hCG as low as 2-10 mIU/mL.
- Not used to confirm pregnancy nor to determine EGA as level range is wide & variable for any GA.
- Serial measurements often used to evaluate suspected ectopic, abortion completion (i.e. when products of conception not visualized following aspiration), or in management of molar pregnancy.
- Other hCG assays in limited availability and use in United States:
- Low sensitivity urine test (detects hCG of at least 1000-2000 mIU/mL)
- Multi-level pregnancy test (MLPT; a graduated urine test).
LAST MENSTRUAL PERIOD (LMP)
- Providers can safely use clinical dating (LMP +/- exam) for most patients with known LMP to determine eligibility for abortion type and setting, compared to the need to determine EDC for a patient continuing their pregnancy.
- First day of LMP alone (+/- 1 week of certainty) is an accurate means of estimating gestational age, with low rates of under- or over- estimation through mid-first trimester (Raymond 2015, Macaulay 2019, Schonberg 2014, Bracken 2011).
|Bimanual exam may improve estimation of gestational age over LMP alone|
|Dating by uterine size in centimeters||
|Dating by uterine size in fruit comparisons||lemon
|Limitations to bimanual sizing:||
*Consider US guidance or additional management