A copper-bearing Intrauterine Device (also known as an IUD, copper-T or coil) can be used after unprotected sex for emergency contraception (EC).
The IUD is a small object that is placed in the uterus; it must be inserted by a trained medical practitioner. The copper IUD is more effective than emergency contraceptive pills (preventing over 99% of pregnancies) and can be left in place for as long as 10-12 years to provide on-going contraception. To function effectively as emergency contraception, IUDs can be inserted up to five days after unprotected intercourse (some studies suggest it can be inserted later).
A systematic review of 42 studies conducted from 1979 to 2011, published in 2012 by Cleland et al in the journal Human Reproduction, found a mean pregnancy rate of 0.09% among 7034 women who had an IUD inserted between 2 and 10 days after unprotected intercourse. The majority of insertions included in the review occurred within 5 days of unprotected intercourse. The authors concluded IUDs were a highly effective method of EC and presented a cost-effective mechanism for both EC and the long-term contraceptive needs of women. However, upfront cost, clinic systems issues, and lack of insurance coverage for IUDs are barriers to widespread IUD for EC use that must be addressed.
Additionally, IUDs do not provide protection against sexually transmitted infections (STIs). For women at low risk of infections, the IUD is a very safe contraceptive method. Women at risk for infection should be assessed by their clinician and in many cases may be able to safely use IUDs after screening.
For more information on IUDs for EC please see our fact sheet on the topic.
Copper IUDs differ from hormonal IUDs (LNG IUD, “Mirena©”), which are not currently recommended for EC use.