Intrauterine device: beyond received ideas

Crédit photo Creative Commons Sarahmirk

More commonly known as the “coil”, the intrauterine device (IUD) suffers from a bad reputation due to a number of misconceptions about it, even though it is actually one of the safest methods of contraception to prevent unwanted pregnancies.

The IUD is a generally T-shaped device that is placed in the uterus. There are two types: copper and hormonal.

Copper IUD

Copper has a spermicidal effect, hence its use for a contraceptive device. There are different sizes of copper IUDs, the smallest being recommended for nulliparous women, that is, women who have never had children (insertion is easier for nulliparous women’s uteri). Depending on the model, this device can be left in place for up to 10 years. According to data published by the World Health Organization (WHO), the rate of women having an unintended pregnancy in the first year of use (in the United States) is 0.8%, while it is 9% with the pill (forgetting to take, gastric problems…).

The copper IUD can also be used as emergency contraception after unprotected sex. Indeed, thanks to copper, the risks of pregnancy are considerably reduced.

Finally, the copper device has the advantage of not using synthetic hormones, which can have undesirable side effects more or less important according to women.

Hormonal IUD

The hormonal IUD has a small reservoir that releases a progestogen hormone in small amounts for 5 years. It works according to the same principle of action of the other progestogenic contraceptives, by acting on the secretions of the cervix which then block spermatozoa. According to WHO data, its efficacy is still superior to the copper IUD, with only 0.2% of unintended pregnancies.

No specific sterility risks

The IUD has long been and often still is called a “stérilet” in french. It owes its name to the fact that it has been attributed cases of infections in the uterus and fallopian tubes that led to sterility among its first users in the 1950s and 1960s. However, studies since then have shown that there is in fact no causal link between IUD use and these infections, since there were ultimately no more women who contracted these infections among IUD users than among users of other contraceptive methods.

Belief in an increased risk of infertility had led to the prohibition of IUD insertion for nulliparous women. This ban no longer applies and was lifted in France in 2004. The doctors do not have to refuse you the pose on the grounds that you have not had a child until then.

To learn more about IUDs (and other contraceptive methods), I recommend Marc Zaffran’s doctor page (in french), also known as Martin Winckler.