How effective is the Copper-releasing IUC for emergency contraception?

The Copper-releasing intrauterine contraceptive device (IUD) is highly effective as a form of emergency contraception. It works primarily by preventing fertilization, creating an inhospitable environment for sperm, and may also inhibit implantation of a fertilized egg. When used as emergency contraception within five days after unprotected intercourse, studies show that it can reduce the risk of pregnancy by more than 99%. This makes it the most effective emergency contraceptive option available.

The high efficacy stems from its mechanism of action and the fact that it can be left in place for long-term contraception after the emergency has passed. For individuals seeking emergency contraception, the Copper IUD not only offers immediate post-coital protection but also provides ongoing contraceptive benefits.

In contrast to other contraception methods mentioned in the choices, such as those that might provide lower efficacy rates, the Copper IUD stands out for its effectiveness in preventing pregnancy when used promptly after unprotected intercourse.