Copper intrauterine device for emergency contraception

The copper intrauterine contraceptive device (IUD) is 99% effective for emergency contraception. It can be inserted up to 5 days (120 hours) after unprotected sexual intercourse, or within 5 days after the earliest estimated date of ovulation (see 'How does EC work?' in the Faculty of Sexual and Reproductive Healthcare Emergency Contraception guideline for advice on date estimation), provided an existing ongoing pregnancy can be excluded (see Starting intrauterine contraception for general advice about excluding pregnancy). A copper IUD is recommended particularly if the individual:

• is taking drugs that induce liver enzymes
• has a body mass index (BMI) more than 30 kg/m² or weighs more than 85 kg
• wants ongoing contraception with the copper IUD.

Organise a follow-up urine pregnancy test 3 weeks after the last episode of unprotected sexual intercourse, and review after next menstrual period to check for complications and provide information about ongoing use. See Follow-up after insertion of an intrauterine contraceptive device.

For more information about the copper IUD, including contraindications and adverse effects, see Intrauterine contraceptive devices.