Mirena is an IUD or intrauterine device that works on hormones. It provides a long-term birth control option for women, and it’s very convenient and easy to use. It’s a T-shaped device made of plastic and is inserted into the uterus. Once inside, it releases the hormone – progestin to prevent pregnancy. Mirena thickens the mucus in the cervix which stops the sperm from getting to the egg. It also thins the uterus lining and suppresses ovulation. It’s one of the IUDs with FDA approval and can prevent pregnancy for up to 5 years post-insertion.

Mirena offers long-term contraception, which is quite effective. Women of all ages can use it. It has quite a lot of benefits such as remaining in place for five years, eliminating the need to stop sex for contraception, can be removed whenever needed, allowing a quick return to fertility. There are no side effects like other birth control methods. Even breastfeeding, women can use Mirena. 

Mirena can decrease bleeding during menstruation after three months or more of use. Around 20% of women can stop bleeding during periods after using Mirena for one year.

Mirena can decrease menstrual pain and pain from endometriosis. The risk of pelvic infection and endometrial cancer is also lower with the use of Mirena IUD

Mirena can be prescribed to women who experience heavy bleeding during periods, along with pain and cramping. Women with fibroid, anaemia, and endometriosis can also be prescribed with this device. If there is abnormal growth of the uterus lining or this lining grows into the muscle wall of the uterus, then also women can be given Mirena to manage this. These are the non-contraceptive benefits of Mirena.

Description of Mirena

Mirena has a T-shaped body made of polyethylene frame. There is a hormone cylinder inside the steroid reservoir around the stem. It holds 52 mg of the hormone and the reservoir has a silicon membrane covering. The body is 32 millimeters long, both vertically and horizontally. A brown polyethene monofilament thread is attached at the end so it can be pulled to remove the device when needed.

The device is packed inside an inserter in a sterile environment. The inserter has a 2-sided body and a slider with a plunger and insertion tube. Once the device is in place, the inserter can be discarded.

Clinical Pharmacology of Mirena

Levonorgestrel is the hormone used in Mirena, and it is a progestin used in man contraceptives. Low doses of this hormone can be released in the uterus through the intrauterine delivery system of Mirena. The hormone has local effects in the uterine cavity. Because of this, there are morphological changes that can be observed in the endometrium such as glandular atrophy, stromal mitoses, etc. Depending on age, medical history, and personal preference one can select suitable IUD. Here’s our post on important factors to consider while choosing your birth control.

Initially, the hormone is released at a rate of 20 μg/day, and then it is progressively reduced to half the value after five years. When women use Mirena, around 505 have their ovulation inhibited. A study for one year found 45% of cycles being ovulatory while after four years, 75% of the cycles were ovulatory. Multiple factors triggered by Mirena can prevent pregnancy, including alteration of the endometrium. 

Pros and Cons of Mirena

Mirena has the following pros and cons that may be experienced by some women.


  • Women do not have to worry about remembering to take the contraceptive daily. It’s a one-time insertion, and it lasts long.
  • It is very effective, more than 99 percent.
  • It can last up to 5 years.
  • Women can continue breastfeeding when they are Mirena.
  • It is a long-term birth control which is also easily reversible.
  • Affordable because most insurance plans have Mirena under their cover.
  • It stops or reduces bleeding in women who experience heavy bleeding and cramps.
  • The hormone doses are lower than some other birth control methods that use hormones.


  • It can be infected during insertion.
  • IUDs may cause ovarian cysts.
  • If a woman becomes pregnant while she is on Mirena can become seriously life-threatening.
  • IUDs don’t protect against sexually transmitted diseases.
  • The insertion can lead to perforation, which is a complication.
  • The device can be expelled from the body leading to pregnancy risk.

When do you Need to Remove Mirena?

Intrauterine devices have to be removed every five to ten years depending on the type and the age you had it put in. Talk to a medical practitioner on the time when the IUD has to be removed. It can also be removed when a woman wants to get pregnant or just doesn’t want to use it anymore.

  • When a woman wants to get pregnant

A woman can have the device removed at any time and fertility will return quickly. It is best to talk it out with a doctor about things a woman needs to do before pregnancy like taking folic acid and the required immunizations. This usually starts at least a month before the IUD removal.

  • If a woman doesn’t want to get pregnant

A woman can have another IUD put in after the old one is taken out. If a new IUD isn’t immediately being inserted, then a woman must start on another contraception at least a week before removal. The best time to remove an IUD is when it is day 1-3 of the woman’s period, the woman hasn’t had sex a week prior to the removal or if the woman has used another contraceptive seven days before removal.

What Happens During Mirena IUD Removal?

If a woman finds the side effects difficult to manage or if the IUD has reached the expiry date, then the device has to be removed. The removal is quite simple and can be done at any time. However, it may be easier during menstrual bleeding as the cervix is softened. If the removal isn’t easy or if there is an intrauterine perforation, then a special clinician can advise on the appropriate removal technique.

  Removal Procedure

  • The removal takes only a few minutes, and many don’t find it very painful. However, consult your doctor if you need to take ibuprofen for cramps before.
  • The woman lies on the examination tables with her legs on stirrups. The doctor would insert a speculum to see the cervix and find the IUD strings as the strings come through the cervix opening.
  • The doctor will pull on the strings and pull the IUD out.
  • The woman must be on birth control while this procedure is happening unless she wants to have children. A new IUD can be inserted in the same appointment.

Symptoms After Mirena IUD Removal

Once the IUD is removed, a woman might feel mild cramping, irritation, bleeding, and sensitivity. The following things may happen after Mirena is removed.

  • Complications in removal: If the removal was complicated and became embedded or implanted inside, then a surgical procedure may be required to remove it. The side effects of this could mean possible infection, spotting, cramping, and tenderness.
  • Menstruation: Usually, when an IUD is placed inside a female body, she may experience heavy or light periods with some cramping. Once Mirena is removed, the periods will return to how they were before insertion.
  • Mirena can delay fertility once it has been removed, but it may not completely inhibit it. If a woman is already pregnant at the time of removal, then it may cause the loss of pregnancy. But if it isn’t removed, then the delivery may be premature.

 Mirena IUD Removal After Care

If a woman feels cramps after the procedure, you can take ibuprofen like Motrin or Advil. If the IUD was removed due to an infection, then you must take the full course of antibiotics.

Final Thoughts

Mirena is a convenient IUD. However, it may not be best for women who cannot use synthetic hormones. This birth control method is quite successful and very easy to sue. The fertility can back soon after its removal as well.

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