Intrauterine devices (IUDs) are a long-birth control option that are inserted into the uterus.

There are two general types of IUDs - copper IUDs, and IUDs that release hormones.

Copper IUDs

Copper IUDs are usually made of a plastic and T-shaped. The top of the T-shape frame holds the IUD in place in the uterus. The bottom of the T is wrapped in thin wire made of an inert metal, usually copper. The copper, or other inert metal, is fatal to sperm. It also promotes the production of a fluid in the uterus that helps to kill sperm. This fluid contains white blood cells, enzymes, prostaglandins, and copper ions.

Hormonal IUDs

Hormonal IUDs are also made of plastic and formed into a similar T-Shape. Like copper IUDs the top of the T holds the intrauterine device in the uterus. The base of the T releases hormones that kill or damage sperm. The hormones also help to thicken the mucus in the cervix making it difficult for sperm to enter the uterus. And finally the hormones prevents the endometrium, the lining of the uterus, becoming thick enough to allow a fertilized egg to implant and grow.

Both types of IUDs are inserted and removed by physicians via simple and quick procedures. They may remain in place for up to 12 years. The pregnancy prevention effects of the IUDs are immediately reversed upon removal of the device.