Is Mirena® contraception right for you?

Pregnancy prevention and active family planning are essential for all women for a significant part of their lives. The average Australian woman experiences her first menstrual period (menarche) at age 13.5, with 10% of girls being under 12 years and 12.5% of girls being older than 16 years at onset. The menopause (last menstrual period) age average in Australia is 51 years, with a majority of women falling in the range between 45 and 60 years. A woman is fertile between these years. Therefore, women have between thirty and fifty potentially fertile years from menarche to menopause.

Contraception will be a concern for every sexually active woman for a significant period over these years, and identifying the right contraceptive method is important for every woman’s health, lifestyle, and wellbeing.

What is Mirena® Contraception?

Mirena® is a hormone-releasing intrauterine device (IUD). The Mirena® contraceptive is a small T-shaped polyethylene plastic device that contains the hormone levonorgestrel in its stem. It has a thin nylon string attached to its base. Placed inside the uterus (womb) by a doctor, with the fine string coming out of the cervix and resting high in the vagina, the device is a long-term, reversible, oestrogen-free contraceptive that can remain in place for up to five years.

This makes Mirena® an ideal choice for women who:

  • Want a long-term, reliable, convenient contraceptive
  • Have completed or are spacing their families
  • Have never been pregnant and do not wish to be in the foreseeable future
  • Are nearing menopause
  • Are breastfeeding
  • Have heavy periods
  • Can’t use oestrogen
  • Have difficulty remembering to take a daily pill
  • Do not wish to use an intravaginal device

How Does it Work?

Levonorgestrel is a synthetic (man-made) version of progestogen. It is also found in oral contraceptive pills and the morning-after pill, as well as subdermal contraceptive implants. Similar to the body’s natural progesterone, levonorgestrel interferes with ovulation, fertilization, and implantation, thus preventing pregnancy.

Placed in the uterus, Mirena® gently and consistently releases levonorgestrel where it is absorbed by the body.

It prevents pregnancy by:

  • Inhibiting the development of the uterine lining so that it is not thick enough to support implantation.
  • Thickening cervical mucus so that sperm can’t pass into the uterus to fertilise the egg.
  • Impacting the movement of any sperm that do make it into the uterus.
  • May prevent ovulation from occurring in some women.
  • The presence of the device itself impacts the environment inside the uterus, making it less conducive to fertilisation and implantation.

Mirena is also prescribed to help with:

  • Heavy menstrual bleeding
  • Some menopausal symptoms
  • Endometrial cancer prevention in women using oestrogen therapy (HRT) by suppressing the effects of oestrogen on the lining of the uterus.

How Does Mirena Compare with Other Methods of Contraception?

This is an extremely reliable, long-term method of contraception. While it requires an in-clinic procedure to insert and remove it, once in place, you can effectively “forget” about it for five years or until you decide to become pregnant (whichever occurs first).

Success rates of Mirena® are reported to be 99.9% and are on par with vasectomy and female sterilisation. (Unlike these, it is 100% reversible). This effectiveness exceeds all other forms of contraception, including the vaginal ring and the combined oral contraceptive pill. Furthermore, after the body becomes used to having a Mirena®, many women report having very light and shorter or no menstrual periods at all while it is in place.

Once Mirena® had been removed, a woman’s cycle and fertility will return to what was normal for her very quickly.

What Else You Need to Know

Some women cannot use hormonal contraceptives, and some women should not use an IUD. Mirena® may be unsuitable for you if you:

  • Have undiagnosed abnormal vaginal bleeding
  • Could be pregnant
  • Have or have had breast cancer
  • Have uterine fibroids or an anatomically abnormal uterus or cervix
  • Are waiting for treatment for cervical changes
  • Have a tumour or cancer in the cervix or uterus
  • Have pelvic inflammatory disease
  • Experience recurrent lower genital tract infections
  • Have an infection of the cervix or uterus
  • Have or had a progestogen-dependant tumour
  • Have or had liver disease or a liver tumour
  • Have congenital heart or heart valve disease
  • Have uncontrolled diabetes
  • Have multiple sexual partners and/or a high risk of STIs
  • Can’t attend follow up appointments after insertion

Your doctor will consider your medical history and advise you accordingly. You must also tell them about any medications you regularly use.

Once inserted, it can take your body a little time to get used to having a Mirena®. Initial side effects may include:

  • Irregular bleeding or spotting
  • Pain
  • Headache
  • Dizziness
  • Hormonal effects such as bloating or skin changes

These should all be temporary.

Some potential but rare side effects need to be assessed promptly by your doctor:

  • Migraine with aura (visual disturbance) that is new to you or worse than previously experienced
  • Severe headaches
  • Increased blood pressure
  • Jaundice (yellowing of the eyes or skin; indicates a liver issue)
  • Blood clots in the legs, lungs, or elsewhere in the body

How Do I Get a Mirena IUD?

The Mirena® contraceptive must be inserted by a specially trained GP like we have at Gynaecology Centres Australia.

You’ll need a pelvic examination before it is inserted, and your full medical history will be taken.

Your Mirena® will usually be fitted within the first seven days of the start of your period or during the hormone-free section of your oral contraceptive pill pack. If you already have an IUD in place, Mirena® can be inserted at any time. You should wait 6-8 weeks after childbirth.

The insertion procedure is quick and via the cervix. This can be uncomfortable or painful and you may elect to undergo intravenous sedation to make it more comfortable for you. This will be discussed at your consultation with us. See more details about this here.

Women’s Health at Gynaecology Centres Australia


We are an essential health service. We remain open, operating as normal, and we comply with all current NSW Health regulations.

We provide comprehensive women’s health services, including but not limited to IUDs and other contraception, cervical screening, breast checks, abortion services, menopause and miscarriage management. We also perform vasectomies for men.

Book with us today for a confidential, judgement-free and empathetic consultation in one of our five locations in NSW and the ACT.
Please call 02 9585 9599 or complete our online booking form.