WHAT IS THE LEVONORGESTREL IUD (Mirena)?
An IUD is a small device which is placed inside the uterus. The vertical arm of this IUD contains levonorgestrel. This hormone is a progestin much like the progesterone a woman’s ovaries produce each monthly cycle. Each week the levonorgestrel IUD gives off about the same amount of levonorgestrel as a woman gets when she takes one or two of the mini-pills called Ovrette. The levonorgestrel causes the cervical mucus to become thicker so sperm cannot reach the egg. Among typical couples who use this IUD, one in 1,000 will experience an accidental pregnancy in the first year.
Mirena is as effective in preventing pregnancy as tubal sterilization and lasts at least for five years. This method has been available for 10 years in Europe and has been used by approximately 2 million women worldwide. In Europe 10-25% of women use an IUD compared to 2% in the United States. Mirena is part of the reason for the popularity of the IUD in Europe.
WHAT ARE THE ADVANTAGES?
- It is the most effective reversible method ever developed!
- It prevents ectopic pregnancies (15 times lower than non-contraceptors).
- It decreases menstrual cramping and dramatically decreases menstrual blood loss (a 97% reduction in menstrual blood loss in one study). but probably about a 90% reduction in blood loss on average). Some women experience an absence of menstrual bleeding after one year (about 20%). This IUD may be left in place for at least 5 years (probably effective for 7 or even more years).
- IUDs are safe, inexpensive over time, and provide extremely effective long-term contraception from a single decision.
- One of the costs of any contraceptive is the cost to you should your contraceptive fail. Given the extremely low failure rate of Mirena, a person using this method is far less likely to have the emotional and financial expenses associated with an unintended pregnancy.
- All you have to do is check for the strings each month (many clinicians no longer recommend this after several months).
- May be used by postmenopausal women on estrogen therapy to protect the endometrium against endometrial cancer.
- Once Mirena is removed, fertility returns immediately. Approximately 8 out of every 10 women who want to become pregnant will become pregnant in the first year after Mirena is removed.
WHAT ARE THE DISADVANTAGES?
- Do NOT start this method of birth control unless you will find it acceptable to have your periods change. They WILL change a lot.
- There may be more bleeding days than normal for the first few months and less than normal after 6 to 8 months. If your bleeding pattern is bothersome, contact your clinician. There are medications which can help you have a better pattern of bleeding.
- The IUD does not provide protection against sexually transmitted infections. Use condoms if there is any risk.
- There may be a high initial cost of insertion.
- There is a slightly increased risk of pelvic infection in the first 20 days after Mirena insertion.
- The risk of uterine perforation at the time of Mirena insertion is also low – between 1 in 1,000 and 1 in 2,000.
WHERE AND WHEN DO I GET A LEVONORGESTREL IUD?
Mirena can be inserted by your clinician or at a Planned Parenthood or health department clinic. Most clinics insert IUDs when a woman has her period or within 7 days of the start of the period. If the risk of pregnancy can be excluded IUD may be inserted at other times in the cycle. |