A 25-year-old woman requests emergency contraception 60 hours after unprotected intercourse. She has a BMI of 32 kg/m². Which emergency contraception method provides the highest efficacy for her?

• A Levonorgestrel 1.5 mg oral, taken as soon as possible
• B Ulipristal acetate 30 mg oral — most effective oral EC up to 120 hours regardless of BMI
• C Copper intrauterine device (Cu-IUD) insertion, most effective EC method at any BMI and up to 120 hours ✓
• D Mifepristone 200 mg oral — licensed for EC in several countries with high efficacy at 60 hours

Explanation

The copper IUD is the most effective emergency contraceptive available with a failure rate <0.1% when inserted within 5 days (120 hours) of unprotected intercourse, and this efficacy is unaffected by BMI. Levonorgestrel EC (A) has significantly reduced efficacy in women with BMI ≥26 kg/m² (and especially ≥35 kg/m²), with the failure rate approximately doubled. Ulipristal acetate (B) is superior to LNG for EC up to 120 hours, but evidence suggests reduced effectiveness in women with BMI ≥35 kg/m², though less so than LNG. At 60 hours and BMI 32 kg/m², UPA would be acceptable if Cu-IUD is declined, but Cu-IUD remains the single most effective option. Mifepristone (D) is used for EC in China but is not licensed as EC in India or UK, making it clinically incorrect in this context.

Reference: Shaw's Textbook of Gynaecology, 17th ed.

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