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How long can copper IUDs prevent pregnancy?

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Blister pack of 28 oral contraceptive pills arranged in four rows, with 21 white active pills followed by 7 orange inactive pills. Arrows indicate the order for taking pills. — birth control A 28-day package of birth control pills.

Copper intrauterine devices (IUDs) are a highly effective form of long-acting, reversible birth control. Depending on the specific product, a copper IUD can provide protection against pregnancy for as long as 10 years.1

These devices function by releasing copper ions that impair the viability of sperm, thereby preventing fertilization. Protection begins immediately following insertion, and the device can be removed at any time, after which fertility typically returns quickly.12