Self-Determination of Eligibility for Medication Abortion Without Ultrasonography Using a History-Based Tool: LMP-SURE.

Objective: To evaluate a self-screening eligibility tool for medication abortion without an ultrasonogram.

Methods: We designed a patient-administered, five-question screening tool (LMP-SURE) that assesses gestational age plus factors associated with misdating or ectopic pregnancy. We recruited participants without prior ultrasonograms from family planning clinics in Alaska, Hawai'i, Idaho, and Utah to complete a brief survey including LMP-SURE and then obtained ultrasound dating by chart review. We compared eligibility for medication abortion by ultrasonogram with eligibility by the LMP-SURE screening tool.

Results: We consented 1,026 participants; 781 met eligibility requirements and completed the tool. Using the LMP-SURE tool, we identified 493 participants (65.1%) eligible for medication abortion without an ultrasonogram. The LMP-SURE tool sensitivity (ability to correctly identify a patient ineligible for medication abortion) was 83.8% (95% CI, 73.1-90.8), specificity (ability to correctly identify a patient eligible for medication abortion) was 70.0% (95% CI, 66.4-73.3), likelihood ratio (-) (probability of someone eligible by LMP-SURE to be ineligible by ultrasonogram vs eligible by ultrasonogram) was 0.23 (95% CI, 0.13-0.40), and percentage of false-negatives was 1.5%. Only 11 patients (1.5%) who met eligibility for medication abortion without an ultrasonogram by the LMP-SURE tool were found ineligible for medication abortion by their ultrasonogram. Of those with conflicts, six (0.8%) had a gestational age beyond 77 days. The two participants (0.3%) diagnosed with ectopic pregnancies both required ultrasonograms by LMP-SURE.

Conclusion: This patient-facing, brief, history-based screening tool can safely minimize the need for ultrasonogram before medication abortion.