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19th Oct 2014

Spotlight On: Contraception… The Contraceptive IUS Coil

We answer all the questions you are too afraid to ask.

Contraception and its many different forms are a talking point for women across the country. With so many different types on the market, coupled with the fact that every woman’s body is different, we take a closer look at all the options that are available to you. 

Last week, we explained all the basic facts that you need to know about the Contraceptive Injection including how it works and how effective it is.

Now, in the first of our two-part feature, we take a look at the Contraceptive IUS (intrauterine system) or Hormonal Coil.


So what is it?

The IUS (intrauterine system) or hormonal coil is a small, T-shaped plastic device that is inserted into your womb (uterus) by a specially-trained doctor or nurse.

How does it work?

The IUS device works by releasing a progestogen hormone into the womb. This hormone helps to thicken the mucus from your cervix, which makes it difficult for sperm to move through to fertilise an egg. It also makes the lining of the womb thinner which means that a fertilised egg is not likely to implant there.

The IUS coil is a long-acting reversible contraceptive. It can work for three or five years depending on the type. Currently, there are two brands used in Ireland, Mirena and Jaydess.

How effective is it?

The IUS coil is more than 99% effective. Less than 1% of women who use either Mirena or Jaydess will become pregnant.

Schedule a check-up: When is the last time you had a medical/dental check-up? Yes, we know that going to the doctor or the dentist is never a pleasant thing and that it can be costly, but honestly? Think of the peace of mind you’ll get knowing that you’re healthy or that you don’t need any fillings. Make a phone call and book a check-up. It’s always important to look after your health.

What are the advantages?

One advantage of the IUS coil is that you do not have to remember to take a pill every day. Therefore you don’t have to think about contraception every day or every time you have sex. It works for five years (Mirena) or three years (Jaydess) and is one of the most effective forms of contraception available.

Other advantages are that the Mirena coil is often used to treat painful or heavy periods and often, women who can’t take the Combined Pill can use this method of contraception.

What are the disadvantages?

The IUS can be somewhat uncomfortable when it is being put in. Some women may not be happy with the way that it affects their periods (see side effects below).

Also, it is extremely important to remember that the IUS does not protect against STIs, so you need to use condoms to protect yourself from this. If you contract an STI and leave it untreated while you have an IUS fitted it could lead to a pelvic infection.

What are the side-effects?

The IUS can make your periods stop altogether or they may become lighter or shorter. However, it is reported that Jaydess is less likely than Mirena to make your periods stop altogether.

Irregular bleeding and spotting can be quite common in the first six months after having it fitted, while some women have reported headaches, mood swings, skin problems or breast tenderness. There is also a small risk of getting an infection after it has been inserted.


Will it make me fat?

To date, there is no evidence to suggest that an IUS will affect your weight.

Will it increase my risk of cancer?

There is no evidence to suggest that having an IUS fitted will increase the risk of cervical cancer, cancer of the uterus or ovarian cancer. Some women may experience small changes in their mood and libido.

When can it be fitted?

The IUS can be fitted at any time during your monthly cycle – as long as you’re definitely not pregnant. Ideally, it should be fitted within seven days of the start of your period as this will protect you against pregnancy straight away.

If the IUS is fitted at any other time, you should use condoms for seven days. After fitting, if you have pain in your lower abdomen, have a high temperature or a smelly discharge you should return to your GP or clinic.