Someone asked us:
How do copper IUDs work? Are they just as effective as regular IUDs?
There are two kinds of IUDs – Mirena and ParaGard. While the Mirena IUD contains progestin, a hormone (like the one found in birth control pills) to prevent pregnancy, the copper IUD is hormone-free. The copper IUD — also sometimes called the ParaGard IUD — works by preventing sperm from reaching the egg. The copper in the ParaGard IUD acts as a spermicide, and the IUD may also prevent the egg from implanting in the uterus.
Most people can use the ParaGard IUD safely. Both types of the IUD are equally and extremely effective — fewer than one in 100 women will get pregnant each year with the ParaGard or the Mirena IUD. The ParaGard, however, is effective for up to 12 years, whereas the Mirena IUD is effective for only five.
-Alex at Planned Parenthood