Mirena is a hormonal intrauterine device (IUD) that has the ability to provide long-term birth control (contraception).
The device is a T-shaped plastic frame that is inserted into the uterus, where it releases a type of the hormone progestin.
To prevent pregnancy, Mirena:
- Thickens mucus in the cervix to stop sperm from reaching or fertilizing an egg
- Thins the lining of the uterus and partially suppresses ovulation
Mirena prevents pregnancy for up to five years after insertion. It's one of several hormonal IUDs with Food and Drug Administration approval.
Why Mirena Insertion is done
Mirena offers effective, long-term contraception. It can be used in premenopausal women of all ages, including teenagers.
Among various benefits, Mirena:
- Eliminates the need to interrupt sex for contraception
- Doesn't require partner participation
- Can remain in place for up to five years
- Can be removed at any time, followed by a quick return to the patient’s normal fertility
- Can be used while breastfeeding — although the health care provider is likely to recommend waiting for about six to eight weeks after childbirth because earlier placement increases the risk of injuring the uterus during placement
- Doesn't carry the risk of side effects related to birth control methods containing estrogen
Mirena can decrease menstrual bleeding after three or more months of use. About 20 percent of women stop having periods after one year of using Mirena.
Mirena can also decrease:
Because of these non-contraceptive benefits, Mirena is often prescribed for women with:
- Heavy menstrual bleeding
- Cramping or pain with periods
- Abnormal growth of the lining of the uterus (endometrial hyperplasia)
- Abnormal growth of uterine-lining tissue into the muscular wall of the uterus (adenomyosis)
Mirena isn't appropriate for everyone. The health care provider may discourage use of Mirena if the patient has:
Tell your doctor if the patient:
Risks related with Mirena Insertion
If the patient does conceive while using Mirena, she is at higher risk of an ectopic pregnancy — when the fertilized egg implants outside the uterus, usually in a fallopian tube. However, because Mirena prevents most pregnancies, women who use it are at lower risk of having an ectopic pregnancy than are other sexually active women who are not using contraception.
Mirena is generally safe. But it's important to remember that:
- Mirena doesn't protect against STIs.
- Rarely, insertion of Mirena causes perforation of the uterus. The risk of perforation might be higher when inserted during the postpartum period.
Side effects associated with Mirena include:
It's also possible to expel Mirena from the patient’s uterus. She may be more likely to expel Mirena if the patient:
- has never been pregnant
- has heavy or prolonged periods
- has severe menstrual pain
- Previously expelled an IUD
- is younger than age 20
- Had Mirena inserted immediately after childbirth
Your doctor may recommend removal of Mirena if you develop:
How the patient will prepare for Mirena Insertion
The doctor will evaluate the patient’s overall health and do a pelvic exam before inserting Mirena. The patient may be screened for STIs.
Mirena can be inserted:
- Anytime during the patient’s menstrual cycle if she is not pregnant. The patient might need to take a pregnancy test to confirm she is not pregnant.
- Immediately after a pregnancy termination.
- Immediately after delivering a baby vaginally or by cesarean section — although insertion immediately after vaginal delivery increases the risk of expelling Mirena.
If the patient had Mirena inserted more than seven days after the start of her period, be sure to use backup contraception for one week.
Taking a non-steroidal anti-inflammatory medication, such as ibuprofen (Advil, Motrin IB, others), one to two hours before the procedure can help reduce cramping.
During Mirena Insertion
The health care provider will insert a speculum into the patient’s vagina and clean her vagina and cervix with an antiseptic solution. Special instruments might be used to gently align the patient’s cervical canal and uterine cavity and to measure the depth of your uterine cavity.
Next, the healthcare provider will fold Mirena's horizontal arms and place the device inside an applicator tube. The tube is inserted into the patient’s cervical canal, and Mirena is carefully placed in the uterus. When the applicator tube is removed, Mirena will remain in place.
The healthcare provider will trim Mirena's strings so that they don't protrude too far into the vagina and may record the length of the strings.
During Mirena insertion, the patient may experience cramping, dizziness, fainting or a slower than normal heart rate.