Dear A European Woman,

You're probably referring to a method of contraception known in the United States as the intrauterine device, or IUD for short. An IUD is a small device that a health care provider inserts into a uterus, through the cervix, as long as a woman isn't pregnant. Some IUDs have a coiled shape, which may explain the German translation that you mentioned. Others, such as the ones available in the U.S., resemble the letter "T."

Today, two types of IUDs are used in the States. Both are approved by the U.S. Food and Drug Administration (FDA). In the past, before the approval of today's IUDs, some women experienced severe complications from certain IUDs. The devices that caused these problems have since been taken off the market. Partly due to its past negative image — and despite its advantages — the IUD is still not as commonly used among U.S. women as it is among women living elsewhere, especially in Europe. More than 85 million women worldwide use IUDs.

While some IUDs are effective for a year, others can last up to twelve years. Depending on the type of IUD, either copper ions or the hormone progestin is released. Copper ions prevent fertilization by immobilizing sperm. Hormonal IUDs not only impair sperm mobility, they also thicken the cervical mucus to help keep sperm from entering the uterus. Both kinds of IUDs change the uterine lining to prevent implantation if an egg is fertilized.

All IUDs have one or more plastic strings at the base that hang down through the opening of the cervix into the vaginal canal. The string(s) need to be checked after each period to be sure that the IUD is in place. It's especially important to feel for the strings every so often during the first few months after insertion — this is when the IUD is most likely to be expelled. If it does come out, contact a health care provider as soon as possible.

As with any method of birth control, the IUD has its advantages and disadvantages.

Advantages

• High level of protection against pregnancy — both types of IUDs are over 99 percent effective
• Long-term protection
• Cost-effective — according to Planned Parenthood, IUDs are "the most inexpensive long-term reversible method of contraception available in the world"
• Allows women to be more spontaneous — there's nothing to insert or put in place before sex
• Privacy — no pills or packaging that can embarrass some women
• Doesn't interfere with sex — neither a woman nor her partner will feel an IUD during sex
• Can be removed at any time by a health care provider
• The copper IUD can be used by women who cannot use hormonal methods of birth control
• Fertility resumes when it is removed, if a woman does not experience certain serious complications from the IUD
• The copper IUD can be inserted for emergency contraception within five days of unprotected sex

Disadvantages

• Needs to visit a health care provider for insertion, follow-up exams (including yearly Pap smears as part of a regular gyn exam), and removal
• Does not protect against sexually transmitted infections (STIs)
• Some women may need to use a back-up method of birth control at first. Copper IUDs are effective right away, but hormonal IUDs are only effective immediately if they're inserted during a woman's period. If they're inserted at any other point during her cycle, it's recommended that she also uses another form of birth control, such as the contraceptive foam, spermicidal jelly, or a condom, if she has vaginal sex in the first seven days after insertion. (Regardless of the kind of IUD used, some women choose to use a back-up method for the first few months in case the IUD accidentally comes out without being noticed.)  
• Some women, especially those who have never given birth, who have heavy periods, or who experience severe menstrual pain, expel the IUD in the first few months. In addition, a woman who has expelled an IUD is more likely to expel it again than a woman who has never expelled an IUD.
• Some women experience complications during and shortly after insertion, including cramping, dizziness, backache, and spotting between periods
• Possible change in menstrual flow, pelvic inflammatory disease (PID), perforation of the uterus, or embedding of the IUD in the uterine lining
• If pregnancy occurs, the IUD must be removed to prevent pelvic infection or miscarriage

The IUD is primarily recommended for women who are in mutually monogamous relationships and at low risk for STIs. While serious complications from IUD use are rare, certain STIs will increase the risk for PID, which, if untreated, can lead to infertility. In particular, women who've had gonorrhea, chlamydia, or PID in the past twelve months shouldn't get an IUD.

If a woman is considering the IUD, and wonders if it's right for her, discussing her and her family's medical history with a health care provider is a good first step. It's also important to read the informational brochure from the IUD manufacturer and talk about the benefits and risks associated with the specific type of IUD that is recommended.

Alice

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