Does a Mirena lead to Weight Gain?

There are pros and cons with everything you introduce into your body and Mirena is no exception. Skyla is a less potent device but works on same principles.

Designed for women as a uterine (womb) stabilizing device (with added benefit of being a contraception) they suit many as the “perfect solution”.


Mirena position in the uterus       The size of a mirena

I have been asked to look into the mirena and weight gain following many patients seeking my help for weight gain (and wondering if the mirena was the cause).

What I discovered in researching for this blog, is that many women, have “unexplained” symptoms and unwanted side effects such as weight gain following the insertion of the mirena but not many link the two together (nor their medical specialist).

My personal journey with IUDs and Mirenas

Before I continue I will share my experience with a mirena.

It is not to scare people, but merely to demonstrate, how even someone in the “know” can become confused about its subtleties.

In 2000 I have my first child. Uncomplicated and natural delivery everything went well. I went back to work early and breast fed and was studying and on it went. After a while, my periods returned when I was 10 months post-partum (after birth of my daughter).

As time went on, my periods became heavier and heavier and my cycle quite short (I was only getting 18 days between not bleeding and bleeding - so about a 25 day cycle).

I became more run down. I also needed contraception as I felt I had enough on my plate. I went and saw the doctor who suggested an IUD. Fabulous. I researched it, it seemed safe and it was put in. It was just before we left for an overseas sabbatical and it seemed like a really good solution to having heavy, irregular periods.

It became apparent about 2 months after having it in that it wouldn’t suit me.

I actually had heavier periods, had loads of pain and discomfort and suffered with low energy levels.

In Scotland, after two weeks of crippling pain, I decided to get it out. I didn’t think about it again and practiced the billings method (the natural withdrawal method) which I guess was successful for a year or two, then I fell pregnant again. (Not a bad thing, just not planned).

We had another beautiful girl but I was sure this time I didn’t want to fall pregnant again as life was busy and full on.  Once again I breast fed for ten months and my periods didn’t kick back for ten months.

Why a Mirena?

Off I went to see the gynaecologist to discuss contraception. He suggested a Mirena.

It made sense, a progesterone impregnated coil that worked locally (in the womb) to stop impregnation. Note the exact way it works is unknown and it doesn’t necessarily stop conception but will impede the embryo embedding. The progesterone it releases is slow-releasing and can last 5-6 years. Progesterone can stabilize the endometrial lining therefor many don’t have periods, or if they have heavy periods, they may lighten.

Statistically 50% of women have lighter periods, 25 % stop all together and 25% aren’t affected. Levonorgestrel is a progestin and of course, the real way it works is unknown.

Basically it is a synthetic progesterone but also has some testosterone properties. It may stop ovulation, stop implantation or stop the movement of sperm. IT is the active ingredient in the “morning after pill”.

The overall benefits of a Mirena are:

  • Contraception

  • To lighten heavy periods

NB: While it is used for heavy periods and often successful it doesn’t fix the causative imbalance that lead to heavy periods, it only Band-Aids the problem.

 What Causes Heavy Periods?

The causative issues for heavy periods can be (which a mirena doesn’t address):

  • Low system progesterone

  • High estrogen

  • Being run down (low base hormones)

  • Low iron

  • and some other causes such as polyps, fibroids etc

I wanted my Mirena to work. It made sense, I had two healthy children, had a stable partner and wanted a break from periods and falling pregnant. However it didn’t suit me.

At first it felt like someone had punched my internal parts (cervix). I was reassured this was “normal” and that it should settle down. I found though it didn’t and sex became very painful. I also spotted for the entire time it was in.

After six months of trying to persevere and spotting, I made the decision to have it removed.

I was never offered a reason why it didn’t suit my body but I suspect my body is one that doesn’t handle “foreign objects” kindly. I.e. my body rejected the Mirena.

Since then I have had another child (almost too easily, despite having PCOS) and made a decision not to go on the pill nor mirena.

For the last year I have consulted women in similar situations, with similar stories and many gaining weight after the insertion of their Mirena.

At first I was putting it down to burn out, babies, changing hormones. From my understanding progesterone should not make your body gain weight. HOWEVER it is becoming clear that in some women it does.

It was when my gynaecologist friends started telling my patients that they see women all the time gaining weight after insertion of the Mirena that I decided to delve deeper. And many gynaes are removing the Mirena as women identify it as the cause of their unexplained weight gain.

When I looked into the side effects of Mirena I was quite shocked. For something that is “sold” as a low risk, safe contraceptive option, it carries a BIG side effect profile.

Side effects of Mirena

This site itemizes the side effects very well. Interestingly there is a center set up to report side effects, possibly because it is so widely used, and also because there are many women experiencing side effects. The more serious side effects of a mirena are:

  • Perforated uterus (serious as it can lead to infection, bleeding and infertility)

  • Ectopic

  • Cysts on your ovaries

  • Pelvic inflammatory disease (PID)

  • Strep B infection

The most common side effects of Mirena are:  missed periods (amenorrhea), bleeding and spotting between periods, heavier bleeding during the first few weeks after device insertion, abdominal/pelvic pain, ovarian cysts, back pain, headache/migraine, nervousness, dizziness, nausea, vomiting, bloating, breast tenderness or pain, weight gain, changes in hair growth, acne, depression, changes in mood, loss of interest in sex, itching or skin rash, and puffiness in the face, hands, ankles, or feet. Sourced from this site.

Synthetic (man made ) progestin can cause stroke in women and I have seen young women with strokes debilitated in wheel chairs after taking progestin pills (weight, smoking, high blood pressure increase your risk).

Adverse Reactions of Mirena

The most common adverse reactions ( ≥ 10% users) are alterations of menstrual bleeding patterns [including unscheduled uterine bleeding (31.9%), decreased uterine bleeding (23.4%), increased scheduled uterine bleeding (11.9%), and female genital tract bleeding (3.5%)], abdominal/pelvic pain (22.6%), amenorrhea (18.4%), headache/migraine (16.3%), genital discharge (14.9%), and vulvovaginitis (10.5%). Adverse reactions reported in ≥ 5% of users are shown in Table 1. Ref Mirena Side Effect Centre Please NOTE the following:

  • Acne affects 6.8%

  • Back pain:7.9%

  • Migraines/headaches:16.3%

Weight Gain and Mirena

WEIGHT GAIN IS 5% (the research sets this at a gain of 20 pounds or 9kg) Obviously there are many other women gaining 2-4 kgs that are not adding to the overall statistic of 5%. Maybe the number is more like 20% but who would know? Ref:

Interactions with Mirena

The Mirena is a pharmaceutical and medical device. It has drug interactions that you need to know about as these things often get missed in appointments. This is a “cut and paste” from here (I am not a medical doctor so ask your doctor, they should inform you of these things).

The Mirena may interact with other drugs, such as insulin (diabetics), steroids and blood thinners such as warfarin.

It has been shown that small levels of the hormones transfer into breast milk and are detectable in babies. I find this possible drug interaction list too high not to mention: Sorry Cut and paste from here: Some MEDICINES MAY INTERACT with Levonorgestrel. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Antifungals (eg, ketoconazole), aprepitant, barbiturates (eg, phenobarbital), bosentan, carbamazepine, felbamate, griseofulvin, HIV protease inhibitors (eg, indinavir), hydantoins (eg, phenytoin), modafinil, nevirapine, oxcarbazepine, penicillins (eg, amoxicillin), rifampin, rufinamide, John's wort, tetracyclines (eg, doxycycline), topiramate, or troglitazone because they may decrease Levonorgestrel's effectiveness
  • Anticoagulants (eg, warfarin) because their actions and the risk of their side effects may be increased or decreased by Levonorgestrel
  • Beta-adrenergic blockers (eg, metoprolol), corticosteroids (eg, prednisone), selegiline, theophylline, or troleandomycin because their actions and the risk of their side effects may be increased by Levonorgestrel
  • Lamotrigine because its effectiveness is decreased, and when levonorgestrel is stopped, toxic effects, such as nausea, dizziness, and vision problems may occur
  • Valproic acid because its effectiveness may be decreased by Levonorgestrel.

My ten cent’s worth here is that St. John’s Wort is used by many as an over-the-counter safe herbal option for managing anxiety/depression and HSV2. It is widely used. I am sure not many would know that the Mirena and St. Johns may interact. The Mirena’s active drug is broken down by the CYP3A4 pathway in the liver.

You can google levonorgestrel for more information. I have quoted reliable medically supported sites. This is another


Whilst the Mirena is in “vogue” at the moment doesn’t mean it is safer than pre and post drug trials. Please weigh it up and don’t get one inserted until researching yourself.

Do you want a synthetic hormone releasing hormones into your body?

Is there another way to either manage contraception, or heavy periods?

Maybe a "healthier" option is to find out why you have heavy periods? Do a saliva hormone test and hair test. I have put together a package here (for Aussie gals only sorry)! That measures hormone levels (estrogens, progesterone, testosterone and cortisol), a hair test and a consultation with me to discuss the results.

It is a game changer for hundreds of women.

>>> Click here <<< to find out more.

One client recently was offered a mirena to reduce her fibroid (while this may assist so will managing her hormones naturally).  She opted to measure her hormones and balance them and the issue started to resolve... naturally and without a mirena (and all the side effects).

I have put this blog together to inform you and encourage you to do your own research before insertion and if things change in your body after insertion that you raise it with your doctor.

Worst case scenario you get it removed. And remember this device does NOT change your systemic hormones.

If you really want to nip the bleeding issue in the bud, I suggest doing a hormone saliva test + hair test (with a consult) which is available from my shop. Discuss with your doctor, discuss with your naturopath and decide a strategy for you. There are many law suits underway in the USA and other places regarding the side effects and adverse reactions of Mirenas.


FDA page about the Mirena
To order your kit click here.