LoveMyLARC-PNG-Vertical-300-White_0The Mirena intrauterine system (IUS), the IUD with the hormone levonorgestrel, is a highly effective method of contraception currently approved for five years. Some data suggests that it probably good for six years, but a new study tells us with a good degree of confidence that the Mirena is safe and effective for seven years. Yes, seven years.

The study was funded by UNDP/ UNFPA/WHO/World Bank Special Programme of Research and published in the journal Contraception. The investigators compared the Mirena IUS head to head against the copper IUD. Almost 4,000 women participated in the study and they were randomized, meaning neither the women nor their physicians were allowed to select the IUD (this helps to remove some kinds of bias). The women were followed for pregnancies and reasons for removal.

By the end of year seven only 0.53% of women with the Mirena IUS had became pregnant versus 2.45% for the copper IUD. There were seven pregnancies among 1,884 women. While the copper IUD is an excellent form of birth control the Mirena was even more effective. In fact, it is far better than any other method of birth control. Based on this data a pregnancy with a Mirena is almost a reportable event, that’s how rare it is. 

Along the way many women had their IUDs removed, typically because they desired pregnancy or had side effects. There were 717 Mirena users who completed six years of follow-up and 398 women who completed seven years with no pregnancies in year 6 or 7. With the copper IUD there were four pregnancies in total in years six and seven. There were slightly more copper IUD users in year six and seven as early removal was more common among Mirena IUD users and this was driven largely by women at the Chinese centers who don’t find amenorrhea (lack of periods), a side effect of the Mirena, to be acceptable. An interesting cultural difference as amenorrhea is more often than not valued by contraceptive users in the United States. 

What also stands out from the study is the absence of ectopic pregnancies in the Mirena arm. Let me state that again because it’s really important, not one women out of the almost 2,000 who had a Mirena had an ectopic pregnancy. Three of the 33 pregnancies with the Copper were ectopic. It’s possible that there were just too few pregnancies with the Mirena to detect ectopic pregnancies, but it’s also possible that either levonorgestrel changes cervical mucus in such a way that sperm has no chance or that the local hormonal effects are as good in the fallopian tube as they are in the endometrium. It’s not really possible to say as he exact method of pregnancy prevention isn’t known. We know it’s not ovulation suppression because by year four 75% of cycles with the Mirena are ovulatory

If a Mirena IUD is $700 for insertion (that’s just an average) in addition to the convenience of extending the lifespan for two more years the cost per year will be $100 instead of $140.

Could he Mirena be good for eight years? The manufacturer was worried that there wouldn’t be enough levonorgestrel for an adequate endometrial effect (one proposed mechanism of action), so a plan to extend the study to eight years was scrapped. Given the lack of pregnancies in year 6 and 7 with the Mirena and a cumulative pregnancy rate of 0.53% one has to wonder if the Mirena would perform better than the copper and its 2.45% failure rate at the end of year eight. 

Bayer has little incentive to prove the Mirena lasts longer. They make money by selling new product. It’s unlikely they will submit to the FDA for a change in product labeling or invest in a study to test efficacy after eight years. Hopefully the WHO will invest in this because the longer a woman can use a highly effective and reversible method of contraception the better. 

So good news! The Mirena is not only the most effective form of birth control and has a stunningly low ectopic pregnancy rate, but it’s also good for seven years!

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  1. I had mine in for 11 years!! Just got it taken out the other day during my tubal ligation. I was under the impression I had a 10year copper IUD so when my son turned 11, I knew I was a year overdue getting it removed. It wasn’t until I went to the sr to set up for my tubal surgery that I discovered they had used the Mirena which at the time was only approved for 5 years!! So I was 6 years overdue to get this thing taken out!!! Thank God it came out effortlessly and not one pregnancy scare over 11 years.

  2. I had mine in for 10 years just got it removed. For some reason I was thinking it was good for 10 years. well it worked for 10 years because I didn’t get pregnant

  3. I have had mine for well over 9 years. I have had my tubes tied but had it inserted to manage flooding periods. It is great I get occasional spotting but nothing compared to what I was getting. I’m 49 so just might leave it.

  4. Woohoo!!! I’ve had my Mirena since June 2012 and still no pregnancy. I was really curious to know if the 5 year recommendation by the obgyn was the end all, be all and was stoked to find this article!! Thanks so much for the info!!

  5. Thank you! I am absolutely tortured each time I change it in or out. Sounds like I am being murdered. I have Ben procrastinating at the 5 1/2 year mark. I now can wait to endure that again. Thank you.

  6. ivehadmy mirena in7.5 years but now started having periods again my current period has lasted over 2 weeks do I need to change it

  7. Around nine years with mine so far, still no period and still no babies. I think I will actually get it replaced this year though.

  8. Great I’m feeling relief, I’m on my fifth year with Mirena and was contemplating removal but now I know I’m save till next two years

  9. I’ve had my Myrena for 8 years now and no pregnancy nor pregnancy scare has happened. I’ve also not had a real period in almost 7 years. This contraception is the most amazing thing that has ever happened to me!

  10. I have had my Mirena in for 8 years now and have no trouble with it. No period, no problem. I think I’ll shoot for 10.

  11. Hi, I’m 53 and have had my 3rd Mirena in for 7 years. Am due to have it replaced but on reading some comments I’m thinking of leaving it for a while longer. Have never had any trouble with it.

  12. I received my Mirena through Washington School of Medicine in St. Louis for a trial after my 2nd pregnancy. I’ve had it 2 months shy of 8 years. It’s been great! No periods, no cramping…but now I’m 28 & want to have another kid. Im scared once it comes out It’ll cause damage or I wont be fertile anymore..8 years is a long time..

  13. This is such good news for me! I am currently on my 4th year using Mirena and, for various reasons, I’m no longer sexually active, so I’m not worried about pregnancy. I love my Mirena because it relieved my previously disastrously heavy periods. given that I’m not worried about an accidental pregnancy anyway, I think I’m going to try leaving mine in longer! thanks for the good information.

    1. My daughter had a Mirena and got pregnant after 5 years. Needless to say she was shocked! Fortunately she had a healthy little girl. She had another one inserted and it’s been 4 years. Is it possible her first one didn’t last long due to her weight? She was heavier then. She had read before they would last 5 years but that was not the case for her!

  14. My Merina is 7 years old and I am just wondering if it is safe to leave it for longer. Hence finding this chain of comments doing my research. I don’t want a new one as I do not want a hormonal device as I am peri menopausal. I have had regular periods just lighter. I am slightly suspicious that it has recently moved which is why I researching whether it is safe to keep them for more than 7 years. It has served me well and I am reluctant to have it removed.

  15. In August of this year,(2018) I will have had my Mirena for 8 years. I havent had a period in 7 years. And no pregnancy. Highly sexually active. No signs of premenopause either. So, I guess it is still working?

  16. Thank you so much for this information. I am currently on my 2nd Mirena IUD. I had my first put in and kept it for the 5 years I believed and was told I could keep it for. I had it removed and the 2nd was placed. Again I believed a 5 year life span. I called to make an appointment to yet get another but was told (last year) that it was good for six! So I am at year 6 Feb 24th, 18. Now I hear they last for 7. I am 41 years old so I know its not impossible to not get pregnant but at least with this new information it buys me another year. I always just wonder if long term having an IUD is not beneficial to my health?

  17. I got my Mirena from Planned Parenthood and when I schedule removal and replacement at year 5, was told I could wait another year. I asked if 13 months would be ok as I would be finishing nursing school at that time. I became pregnant exactly 6 years to the month of original insertion. I didn’t find out until I went in this past December and had a positive pregnancy test (but had been bleeding 14 days). Went to ER knowing risk for ectopic with iud, and found we lost the baby. PP acted like it was due to the month past the 6 year mark (when they had told me it was ok). Since it is outside the perimeters of the 5 year published approval, should I report the pregnancy to any agency or company for research data or not?

  18. I am so glad I read the comments because I’m at 8.5 years on my second Mirena and don’t want to take it out. I’m 45, no periods, husband has been snipped (but never tested…and I’m not willing to find out the hard way) and no complications. I may just carry on as usual. I would guess once the hormones wear out completely that a period may resume? Maybe not.

  19. I have had my ParaGuard in for 10 years, I have had 2 kids, I just turned 50 & still have my period. I have never any problems with my IUD, but do I really have to get it out & have another put in to wait until I reach menopause? My periods did become heavier for a few months, so I was worried about IUD not working anymore, but after reading some info, I feel like leaving it in until my periods are gone.

  20. I had the mirena in for 10 ½ years and it worked perfectly. I never had a period…the entire time. Never got pregnant. But ladies, let me warn you. As soon as you have the mirena removed, you will be fertile myrtle. My suggestion. One comes out and another goes in. Unless you are trying to conceive and then you are good to go. By the way this is 100% of personal experience.

  21. Thanks for posting Dr Gunter. I just looked at my expiry date on the booklet my gynecologist gave me and I’m more nearly 4 months past the five year mark so started to panic! Off to have a chat with my gynecologist about whether I should get it replaced – will refer to this study.

  22. I had my son in January 2002. Mirena march.m 2005. 15 years later I still have it in. With no problems

  23. This is all very helpful. I’ve had my Mirena for 6.5 years. I saw an ob/gyn at 5 years and was told not to rush replacement, it’s good for longer. Does anyone have links to information on maximum time before replacement besides for birth control?
    I am not currently sexually active, so the key benefit of my Mirena is no periods. Can I leave it until periods resume, or is there any other reson to replace?

  24. I’m sure doctors would be horrified but I kept my Mirena in for 13 years. I wasn’t having periods and I didn’t want anything to change that. I did not remove it untill my periods resumed. I never had any complications during that time either.

    1. 15 years for me. My on stated I was messing up the research. I was one of the first people to get it in my areA

    2. I have had my Mirena for 11 years. I am still not having menstruals. I want to get it removed and replaced, but I am afraid of the pain. I would love to know what level of pain and discomfort was associated with the removal of your Mirena.

  25. I have had my Mirena for 12 years *married, monogamous, annual paps, mammograms & minimal risk factors for reproductive cancers or any life-threatening illnesses. My point- I felt I was extremely LOW-RISK for any infections, STDs or physical complications arising from my decision to go against recommendation of 5 year removal plan.*
    I am just recently starting to ovulate and I have had one menstrual cycle that lasted a full three days that required no more than a panty liner to manage. Prior to Mirena I needed RX Ponstel and Tylenol #3 for 8 days of HELL. Based on my slow return to cycling compared to my barely manageable previous cycles(age 9-30) I’m confident the amount of hormones in the IUD and their effectiveness FOR ME have remained steady for 12 years.

  26. GOSH DANGIT I could have hung on to mine for another 2 years. My husband was freaking out and refused to have sex from the official 5 year expiry date, until I got a new IUD (despite me yelling “You’re a biomedical engineer, you know expiry dates don’t work like that”). I got it replaced with the copper one for reasons of being a cheapskate (living in South Africa, on student insurance that only covers the copper T) and am regretting it because of the heavier periods.

  27. I just had my mirena removed today after 8 years and ten months. I had complete amenorrhea for the entire time (minus the first 6 months when it was gradually decreasing).

  28. What do you think about keeping Mirena 8 years rather than 7? Seems like from your post that it’s entirely possible it’s effective into year 8 as well, they just abandoned the study.

    1. I’m thinking it is worth trying.
      And then, armed against the future, start working with young people so that in two years and four years, you don’t have to worry about that 8th year. Midterms matter. If people under 30 actually vote, they’ll all be thrown out.

  29. I would love to learn more about amenorrhea. I have asked several OB/GYNs if it is safe, and they all say yes, but without an explanation. I have been wanting to try a new birth control that allows amenorrhea, but am afraid it’s unhealthy or will lead to side effects later in life. I think this would make a great blog post, and would love to hear your feedback.

    P.S. – I am subscribed to your blog and always love reading your posts when they hit my inbox!

    1. With hormonal contraception like Mirena, the lining of the uterus becomes so thin that there is nothing to slough off, hence, no period. This has no long term effects so once the device is removed, the lining begins to thicken again, with a return to normal menstrual cycles. There is nothing unhealthy about this, and in fact, for many women with heavy periods, this cures their iron deficiency anemia.

  30. Back in 2013, my ob/gyn preceptor was recommending his patients use their Mirenas up to 7 years. I’m not sure what data was available then, but he said it was common practice in Europe. I’d love to keep my Mirena longer (insertion was the only not-fun part of Mirena for me), so I’m glad there is this data to back up the 7 year recommendation.

    My favorite question I get asked about amenorrhea is, “Since you don’t have a period, how do you know you’re not pregnant?” Uhh… because I have a Mirena. I understand why a general public person would ask this question, but it’s a bit concerning when a healthcare provider asks it.

  31. Excellent information. Thank you for posting. It would be wonderful if more women around the world were able to avail themselves of the Mirena.8

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