Over 99% of women using the Mirena coil avoid unplanned pregnancy. It’s one of the most reliable contraceptive methods available today. As a medical professional at The Women’s Clinic, my private menopause and contraception clinic in Edinburgh, I help women understand what this remarkable hormonal coil is capable of.
The Mirena coil works as an intrauterine system (IUS). It releases levonorgestrel, a synthetic progestogen hormone, directly into your womb. This hormone delivery has multiple protective effects throughout your reproductive system.
The device prevents pregnancy by thickening your cervical mucus. This makes it nearly impossible for sperm to reach an egg. It also thins your uterine lining, creating an environment unsuitable for implantation. I specialise in fitting these devices and I have witnessed first-hand their effectiveness in providing long-term contraception and treating various gynaecological conditions.
Key Takeaways
- The Mirena is a T-shaped plastic frame releasing levonorgestrel hormone directly into the womb
- It achieves over 99% effectiveness through multiple mechanisms of action
- The device thickens cervical mucus to prevent sperm from reaching eggs
- It thins the uterine lining to prevent implantation
- This intrauterine system provides long-term contraception and treats a number of gynaecological conditions
- The Women’s Clinic in Edinburgh specialises in professional Mirena fitting
How it works for contraception
The Mirena coil is a reversible method of contraception that operates through a multi-layered defence system. I often tell my patients it’s more effective than many other options. This is because it’s designed to work comprehensively.
It releases levonorgestrel hormone directly into your womb. This hormone thickens your cervical mucus, creating a natural barrier. The thickened mucus makes it extremely difficult for sperm to get through your cervix and reach an egg for fertilisation.
Secondly, the hormone thins your womb lining, known as the endometrium. This creates an environment that’s unsuitable for a fertilised egg to implant and develop. The thinned lining serves as an additional protective measure against pregnancy.
In some women, the Mirena can also partially suppress ovulation. But this isn’t its primary contraceptive mechanism. The combination of these three actions makes it difficult for sperm to reach their target while creating an inhospitable environment for pregnancy.
With over 99% effectiveness, the Mirena is one of the most reliable contraceptive methods available. Unlike the contraceptive pill, which requires daily attention, this method offers long-term protection for up to eight years. It’s an excellent choice for women seeking dependable, hassle-free contraception.
How it works for heavy periods
Heavy periods can significantly disrupt your daily life. The Mirena coil offers a highly effective first-line treatment. NICE recognises the Mirena as a primary treatment for heavy menstrual bleeding, providing women with confidence in its clinical effectiveness.
The levonorgestrel hormone in the Mirena directly targets your womb lining. This hormone dramatically reduces the thickness of the uterus lining throughout your menstrual cycle. With a thinner lining, there’s less tissue to shed during menstruation.
This targeted approach transforms heavy bleeding into manageable or minimal flow. Many women experience periods that become significantly lighter within the first few months. Some even find their menstrual bleeding stops completely, which is perfectly safe and reversible.
Clinical studies demonstrate remarkable results – the Mirena can reduce menstrual blood loss by over 90% within six months of insertion. This isn’t just about convenience; it’s genuinely life-changing for women who previously suffered from debilitating heavy periods.
In my practice, I’ve seen patients regain control of their lives after a Mirena insertion. Women who once experienced flooding, severe period pains, and anaemia from excessive blood loss find themselves free from these concerns. The transformation often extends beyond physical symptoms – many patients report improved energy levels, better sleep, and renewed confidence in their daily activities.
The beauty of this treatment lies in its precision. The Mirena thins the lining locally within your uterus, creating light bleeding or stopping periods altogether. This is done without affecting your entire hormonal system, maintaining your natural hormone production.
How it works as hormone replacement therapy (HRT)
As a menopause specialist, I often suggest the Mirena coil for hormone replacement therapy to my patients. Menopause leads to a natural decline in progesterone levels, causing hormonal imbalances. These imbalances can significantly impact your overall wellbeing.
When you’re on HRT, taking oestrogen requires progestogen to protect the lining of your womb. Without it, the womb lining can grow too thick, posing serious health risks. The Mirena coil releases levonorgestrel, a synthetic hormone that acts as this vital progestogen.
The Mirena’s targeted delivery system sets it apart. Unlike daily tablets, it releases hormone directly into your uterus. This method ensures you receive lower doses of synthetic hormone. Yet, it provides complete protection for your endometrium.
This direct delivery system maintains the lining at the right thickness, preventing endometrial hyperplasia. The hormone’s local action means fewer side effects compared to oral progestogen tablets.
The Mirena is licensed for five years when used in HRT, making it a practical long-term option. It eliminates the need for daily progestogen tablets. This offers consistent, reliable protection throughout your menopause journey.
Are there any side effects?
I always discuss the possible side effects of the Mirena coil with my patients before insertion. Being informed helps manage expectations and reduces anxiety about what to expect during the adjustment period.
The most common side effect is irregular bleeding or spotting, which can continue for up to six months after your coil is fitted. This may include a brown discharge that appears between periods. This is completely normal as your body adjusts to the hormonal changes.
Other side effects I commonly see include breast tenderness, headaches, acne, and PMS symptoms. These effects are typically most noticeable during the first three months. Most women find these symptoms settle as their body adapts to the hormone.
I reassure my patients that these temporary changes are part of the normal adjustment process. Your body needs time to respond to the steady release of the synthetic hormone from the coil.
About 20% of women stop having periods entirely after one year of using the Mirena coil. Many find this liberating, though some initially worry about the absence of periods. I explain that this is a safe and expected effect of the thinned womb lining, not a cause for concern.
The irregular bleeding and spotting usually improve significantly after the first few months. If you experience persistent or concerning symptoms, I always encourage patients to contact their healthcare provider for reassurance and guidance.
There are other risks associated with its use, including expulsion and perforation. Expulsion which occurs in less than 4% of insertions is when the coil is partially or completely expelled from the uterus. This can happen during the start of your period or due to cramping. This can lead to unintended pregnancy if the coil is not in place. Additionally, there is a small risk of perforation, where the device may penetrate the uterine wall during insertion. This can cause serious complications and may require surgical intervention.
Is Mirena coil effective immediately?
Many patients inquire about the Mirena coil’s effectiveness right after insertion. The response hinges on the timing of your fitting appointment.
Inserting your Mirena during your period or within seven days of its start makes it effective immediately. This ensures you have instant protection without a waiting period.
Yet, if insertion happens more than seven days post-period, the Mirena isn’t effective right away. In such cases, you’ll need additional contraception for a full week post-procedure.
During this initial week, I advise using condoms for any sexual activity. This step prevents unintended pregnancies while hormone levels in your system increase.
There are exceptions to these timing rules. If you get the Mirena immediately after childbirth or a pregnancy termination, it offers instant protection, regardless of timing.
I ensure my patients receive clear written instructions on when their protection starts. Knowing these timing details is vital for your peace of mind and avoiding any confusion about your protection status.
How is the Mirena coil fitted?
Many women feel anxious about the Mirena coil insertion. But, the good news is that the fitting process is remarkably similar to having a routine cervical smear test. Most of my patients are pleasantly surprised by how straightforward it is.
During your appointment, you’ll lie comfortably on an examination couch. I use a speculum to visualise your cervix clearly. Then, I clean the cervical area with antiseptic solution to ensure sterility throughout the procedure.
I use a small measuring device to determine the exact depth of your uterus. This measurement is critical for ensuring the plastic t-shaped device sits in the optimal position once it’s been fitted.
The Mirena comes pre-loaded in a thin introducer tube. I gently pass this through your cervical canal into your uterus. Once in position, I release the coil from its applicator and remove the introducer tube.
Lastly, I trim the threads attached to the Mirena so they sit comfortably within your vagina. These threads will allow for easy removal when the time comes, typically after five years.
I always recommend taking your usual painkiller about one to two hours before your appointment. Some women experience period-like cramping during insertion. But the entire procedure typically takes just a few minutes. At The Women’s Clinic, we specialise in making this process as comfortable as possible. I’m always happy to explain each step as we go along.
How long does the Mirena coil last?
The lifespan of your Mirena coil hinges on its purpose. I always discuss this with my patients, as the licensing varies based on their needs.
For contraception, the Mirena is now licensed for eight years. This makes it a top choice for long-term contraception, requiring minimal upkeep. The extended lifespan means fewer visits to the clinic and consistent protection.
Yet, if it’s for treating heavy periods or hormone replacement therapy, it must be replaced after five years. This is due to the specific hormone levels needed for these treatments.
Smaller coils like Kyleena and Jaydess are designed for contraception only. They lack the hormone needed for womb lining protection during HRT.
The Mirena system’s advantage lies in its consistent release of small amounts of hormone over these extended periods. This ensures effectiveness without the need for daily care, making it a practical long-term option.
The Women’s Clinic, Edinburgh: A private menopause and contraception clinic
At The Women’s Clinic in Edinburgh, we focus on sexual health services, with a specialisation in the Mirena coil. Our private clinic recognises the importance of personalised care in reproductive health decisions. We understand that women seek tailored solutions for their health needs.
I offer fitting services in a welcoming, professional setting. I take the time to discuss how the Mirena can benefit you. Whether it’s for contraception, managing heavy periods, or menopause support, I’m here to help.
As a private clinic, we offer flexible appointment times and in-depth consultations. We believe every woman deserves clear explanations about her treatment options.
If you’re looking into the Mirena coil or need specialist women’s health advice, our Edinburgh clinic is ready to support you, providing compassionate, professional care tailored to your unique needs.
