Gynaecologist Perth | Mirena


Intra-Uterine Contraception Device (IUCD)

Mirena is an intra-uterine contraceptive device (IUCD), also known as an intra-uterine device (IUD). It releases progesterone directly into your uterus to prevent pregnancy. It is also widely used to treat heavy menstrual periods.

What is the Mirena implant?

The Mirena is an intra-uterine contraceptive device (IUCD). The use of these devices dates back for centuries but, before the Mirena, they made periods heavier and more painful.

View Mirena image

The Mirena is unique in that it makes your periods lighter. Commonly, it often makes them stop.

Why does this happen?

The Mirena is impregnated with progesterone hormone in a matrix. The progesterone is released at a relatively constant rate over a long period of time, lasting five or more years.

By releasing the progesterone locally within the uterus, it inhibits the growth of the lining of the uterus. So, your periods become lighter or non-existent

It does release some progesterone into general circulation, but the dose is very small. In fact, it is barely measurable and so, this usually will not produce any progesterone side effects.

Mirena implant |Dr Chris Nichols

What is the Minera used for?

As the IUCD name suggests it is a contraceptive — and a very good one. It is also referred to as the Mirena IUD. With this method of birth control, you have even less chance of pregnancy than with oral contraceptives.

Because of its capacity to control the menstrual period, it also has a major use in controlling heavy periods. In fact, it has been so effective that hysterectomy rates have dropped dramatically.

It also plays a role in managing menopause. It provides a simple method of protecting the endometrium when using oestrogen to control menopausal symptoms.

Mirena implant side effects | Dr Chris Nichols Perth WA

What are the Mirena side effects?

There are some side effects that may be associated with the Mirena coil:

Mirena insertion

The Mirena contraceptive device is a little fussy to put in. It is usually inserted under local anesthetic in the consulting rooms. However, when there are problems with the period, I will commonly insert it in theatre under general anesthesia. This way, I can also check the cavity of the uterus during the procedure.

Pelvic infection can occur after insertion. This is uncommon, but still possible.

Mirena bleeding or spotting

The biggest negative is that it takes time to achieve control of the lining of the uterus. Typically after insertion, there will be spotting or irregular bleeding for many weeks.

There are many negative comments about the Mirena on the internet. They reflect two issues:

  1. Firstly, many people give up on the device too early. They may not be tolerant or aware of the settling-in period. But for persistence, many women will be rewarded.
  2. Secondly, this is a widely used type of contraception. Therefore, there may be more online complaints as there are generally more people using it. A very small percentage of unhappy people adds up to a lot of complaints that are not removed.

Mirena removal

There are strings connected to the device that protrude through the cervix. If they are too long they can be a problem. In this case, you may be able to feel the strings. They can also retract into the body of the uterus, making removal of the device difficult. That said, removal is usually very easy, even easier than a regular pap smear.

Mirena hormones

Progesterone side effects can be a problem for some women. These can be annoying but are rarely serious. They include: weight gain, acne, mood changes, and breast tenderness. However, with such a small dose of progesterone released, these side effects are uncommon.

Mirena weight gain is possible as a progesterone side effect but, because of the low dose in the system, this is unlikely. If considered in context, a Mirena will commonly be inserted during the late 30s and early 40s. This is a time when weight gain is not uncommon anyway, related to lifestyle change and loss of muscle mass.

Not a suitable option

Sometimes this intrauterine contraception device just does not work. In cases of a bigger uterus, fibroids, or a uterus with an unusual shape, it may not control the periods.

It is also important to note that any intrauterine device, including the Mirena, will not protect against sexually transmitted disease.

Should I get the Mirena implant?

I am happy to discuss if this is a suitable contraceptive method for you, or recommend other alternatives. For example, some women may prefer oral contraceptives or a non-hormonal IUD.

Get in touch

Dr Chris Nichols Obstetrician - Gynaecologist - Fertility Specialist Perth

Dr Chris Nichols

I deliver babies at SJOG Murdoch Hospital and have gynaecology theatre lists at both Murdoch and South Perth Hospital. With the help of Fertility Specialists of WA, I established the first fertility clinic south of the river, Fertility Specialists South, located in Applecross.
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