Want to know more about the hormonal coil, including side effects? Dr Clair Crockett, GP, menopause specialist and trained coil fitter answers your questions
The Mirena is an intrauterine system (IUS), made of plastic, that can be used to treat heavy or painful periods, as a contraception, and as the progestogen part of hormone treatment (HRT), although it does not have the benefits of natural progesterone.
Many women wonder how having a Mirena coil or another brand of IUS might affect them – here are some questions we commonly hear:
What are the side effects of a Mirena coil?
The Mirena coil can cause some irregular, light bleeding. It can lead to spotting or having a brown discharge that may continue for up to six months. After this time, it usually settles down and then there is usually no further bleeding.
It used to be thought that a hormonal IUS worked only locally – in the womb - but research has shown that there is significant absorption of the synthetic progestogen, levonorgestrel, through the bloodstream into the whole body, even within 15 minutes of it being inserted. This means there is potential for side effects across the whole body.
Some women experience side effects such as acne, weight gain, hypertension, fluid retention, headaches and abdominal pain [1]. Other possible side effects include ovarian cysts (these are usually harmless) and a small chance of getting recurrent thrush [2].
If you have a progestogen intolerance or sensitivity, you may prefer to take progesterone (such as Utrogestan), which has the same chemical structure as the progesterone your body naturally makes and is less likely to cause a negative reaction.
Will a Mirena coil help PMS?
While a hormonal intrauterine system (IUS) such as Mirena is recommended as a treatment for heavy or painful periods as it usually makes them lighter or shorter, and can stop ovulation in some women, it does not usually help premenstrual syndrome (PMS) symptoms. However, a few women may find that it lessens their PMS symptoms by stopping ovulation. In some women, the Mirena can cause some PMS symptoms, particularly in those who are progestogen intolerant. Many women with PMS and PMDD benefit from being prescribed natural, bioidentical hormones.
RELATED: All about progesterone: PMS, PMDD, postnatal depression and menopause
Will a Mirena coil stop my periods?
According to the manufacturer of the Mirena, about two out of 10 women stop having periods after one year of Mirena use. Most women find that their periods and any bleeding stops after 3-6 months of having the Mirena inserted.
Can a Mirena cause weight gain?
Some women have reported that they have gained weight after having it inserted. This is likely related to the way that the synthetic progestogen blocks natural hormones such as progesterone and estrogen working in your body.
RELATED: Will HRT make me gain weight?
Can a Mirena cause hot flushes?
Hot flushes during perimenopause and menopause are caused by fluctuating hormone levels. As the synthetic progestogen can block natural hormones, some women who have had a Mirena inserted experience menopausal symptoms, including hot flushes.
Can a Mirena cause headaches?
Headaches are one of the more common side effects of the Mirena coil. They usually settle within the first few months of the Mirena being inserted.
RELATED: Headaches and menopause: what’s the link?
Can a Mirena affect my mood?
Some of the most common side effects of the hormonal IUS are those affecting mental health – low mood, anxiety, intrusive thoughts, reduced concentration and low energy [3,4]. These symptoms can occur months after the IUS has been inserted [5].
Unfortunately, many women who report mental health side effects of the Mirena or other IUS have their experiences dismissed, often because of the lack of understanding of how the IUS works. We now know that there is significant absorption of synthetic progestogen through the bloodstream into the whole body.
Can the Mirena affect my skin?
Just like with the contraceptive pill, hormonal acne is a known side effect of the Mirena coil – both for those who have and haven’t previously experienced it. This is because the increase in progestogen can affect levels of other hormones. Breakouts usually occur a couple of months after insertion and can often ease as the amount of progestogen the Mirena coil is releasing plateaus in months 3-6. Some women find that breakouts do not settle and choose to have their coil removed. Breakouts tend to then resolve once the progestogen from the coil is no longer being released into their body.
Is the Mirena hormone treatment (HRT)?
Mirena is not a full hormone treatment on its own. Usually, most women are prescribed progesterone, estradiol and testosterone to improve their perimenopause or menopause symptoms. Because the Mirena contains a synthetic progestogen rather than bioidentical progesterone, increasingly women choose to take additional progesterone alongside having a Mirena. This is because progesterone works throughout the body, not just in the uterus, and provides additional benefits, beyond just uterine protection.
RELATED: Utrogestan (micronised progesterone) explained
Is having a Mirena fitted painful?
While many women do not feel any pain when having a coil inserted, most do find it uncomfortable. You can expect some period-like cramping during and after the fitting. Sometimes this can be quite severe around the time of the fitting, but is usually very short lived.
Remember, you can take paracetamol and ibuprofen an hour before the fitting, and you should ask your clinician about numbing cream or local anaesthetic spray, gel or injection. You can also ask to pause or stop the fitting at any time.
Can I use Utrogestan if I have a Mirena coil?
Women can continue to experience symptoms of low progesterone after having a Mirena coil fitted. Some women find that taking Utrogestan while they have a Mirena coil can be very helpful to improve symptoms as well as to improve future health. Utrogestan is natural, bioidentical progesterone that can help reduce inflammation, relax muscles, improve sleep and symptoms of anxiety.
Resources
CoSRHClinical Guideline Intrauterine Contraception
