What is the effectiveness rate of the IUD for emergency contraception?

The effectiveness rate of the intrauterine device (IUD) as a form of emergency contraception is approximately 99%. This makes it the most effective method available for preventing pregnancy after unprotected intercourse. The IUD works by preventing fertilization and may alter the uterine lining to prevent implantation if fertilization occurs.

When considering other methods of emergency contraception, such as pills containing levonorgestrel or ulipristal acetate, their effectiveness rates are lower—typically around 85% and 90% respectively. Therefore, the IUD stands out for its high efficacy, especially when inserted within five days after unprotected sex.

Understanding the importance of timing and the mechanism of action is critical for both practitioners and patients when discussing options for emergency contraception. The 99% effectiveness rate underscores the IUD’s reliability, making it the preferred choice for those seeking immediate and highly effective contraception in emergency situations.