The IUD, or intrauterine device, is an object that is inserted into the uterus. It is one of the most effective forms of birth control, guaranteeing more than 99 percent effectiveness. There are two general kinds of IUDs. One is the copper IUD and the other is the hormone-releasing IUD. In the United States, the term IUD is often used to refer to both kinds. The hormone-releasing IUD can be called IUS, or intrauterine system.
So how does the IUD work? Obviously, the copper IUD works in a different way than the hormone-releasing IUD. The copper IUD’s effectiveness lies in the copper content. The fact is that the copper in the IUD serves as a natural spermicide. Depending on the specific kind of IUD that you use, the copper can be wrapped around the tube or it can come in form of copper beads placed along a string. In addition to the spermicide action of the copper, the IUD also stimulates the production of white blood cells in the uterus. This results in the uterus not being conducive to eggs and sperms, further lessening the chances of getting pregnant. Copper IUDs are effective for five to ten years.
When it comes to hormone-releasing IUDs, the mechanism of action is quite different. The IUD itself is made of plastic. It has an interior cylinder, which serves as a container for the hormone that is to be released gradually over a period of time. In this sense, this type of IUD functions much like birth control pills. This type of IUD works for about five years.