Effectiveness
Copper IUDs are a form of long-acting reversible contraception and are considered to be one of the most effective forms of birth control available. The type of frame and amount of copper can affect the effectiveness of different copper IUD models. The failure rates for different models vary between 0.1 and 2.2% after 1 year of use. The T-shaped models with a surface area of 380mm² of copper have the lowest failure rates. The TCu 380A (ParaGard) has a one year failure rate of 0.8% and a cumulative 12-year failure rate of 2.2%. Over 12 years of use, the models with less surface area of copper have higher failure rates. The TCu 220A has a 12 year failure rate of 5.8%, whereas the TCu 380A has a 12 year failure rate of 2.2%. The frameless GyneFix also has a failure rate of less than 1% per year. Worldwide, older IUD models with lower effectiveness rates are no longer produced.
Unlike other forms of reversible contraception, the typical use failure rate and the perfect use failure rate for the copper IUDs are the same because the IUD does not depend on user action. A 2008 review of the available T-shaped copper IUDs recommended that the TCu 380A and the TCu 280S be used as the first choice for copper IUDs because those two models have the lowest failure rates and the longest lifespans. The effectiveness of the copper IUD is comparable to tubal sterilization, which has a first year failure rate of 0.5%. However, the effects of the copper IUD are reversible, which can be viewed as either an advantage or a disadvantage, depending on a woman's goals for contraception.
Read more about this topic: IUD With Copper