A Study to Evaluate the Safety and Initial Efficacy of a Spherical Copper Intrauterine Contraceptive Device the IUB(tm)

A copper IUD (intrauterine device or coil) is a type of intrauterine contraceptive device. Most IUDs have a plastic T-shaped frame which is wrapped in copper wire and sleeves. The device has to be fitted inside and removed from the uterine cavity by a doctor or qualified medical practitioner. It remains in place the entire time pregnancy is not desired.

The IUD is a long acting reversible contraceptive, with different IUDs intended to last for different lengths of time, usually between 3 and 10 years. The length of time that the device lasts depends mainly on the amount of exposed copper, which is indicated, in square millimeters, by a number in the name of each device (i.e., the Paragard T-380A has 380 square millimeters of exposed copper).

The IUD is the world's most widely used method of reversible birth control, currently used by over 175 million women.

The mechanism of IUDs is not well understood. It is known however that the presence of a device in the uterus prompts the release of leukocytes and prostaglandins by the endometrium. These substances are hostile to both sperm and eggs; the presence of copper increases the spermicidal effect. The general medical consensus is that spermicidal and ovicidal mechanisms are the only way in which IUDs work. Some physicians and medical texts have suggested they may have a secondary effect of interfering with the development of pre-implanted embryos; this secondary effect is considered more plausible when the IUD is used as emergency contraception.

Second-generation copper-T IUDs have failure rates of less than 1% per year, and cumulative 10-year failure rates of 2-6%. A copper IUD may also be used as emergency contraception. If an IUD is inserted within five days of unprotected intercourse, a woman's chance of pregnancy is reduced to that of ongoing IUD users.