A B C D E F G H I J K L M N O P R S T U V W

INTRAUTERINE SYSTEM

What is an Intrauterine System ?

An IUS is a small T-shaped plastic device which contains the hormone progestogen. A trained doctor or nurse will put it into your womb. The IUS slowly releases the progestogen hormone. An IUS works for up to five years. The first IUS available in this country is called Mirena. Not everyone can use an IUS and your doctor or nurse will need to ask you about your own and your family's medical history. Do mention any operations or illness you have had.

How does an Intrauterine System work ?

It thickens the mucus at the entrance of your womb (cervix). This makes it difficult for sperm to move through it and reach an egg. It also makes the lining of your womb thinner so it is less likely to accept a fertilised egg. In some women it stops the ovaries releasing an egg (ovulation), but most women who use an IUS ovulate.

How effective is an Intrauterine System ?

Out of every 100 women who use an IUS, less than 1 woman will get pregnant in a year.

What are the advantages of an Intrauterine System ?

It works as soon as it is put in, works for five years and does not interfere with sex. After you have used an IUS for about three months or so your periods usually become much lighter and shorter, so an IUS can be useful if you usually have very heavy painful periods. It usually reduces or gets rid of period pain. Your usual fertility returns quickly when the IUS is removed.

What are the disadvantages of an Intrauterine System?

Most women haveslight irregular bleeding between their periods, for the first three months or so. This can be annoying, but should settle down. You may get temporary side-effects such as headaches, acne and breast tenderness. If you do get any of these they usually go away after a few months. Some women may have cysts on their ovaries in the first few months. These are not dangerous and do not usually need to be treated. Often there are no symptoms, but some women may have pelvic pain. These cysts usually disappear without treatment. The womb can push the IUS out (expulsion) or it can move (displacement). This is most likely soon after it has been put in and you may not know it has happened. This is why your doctor or nurse will teach you how to check the threads of your IUS every month. Rarely, the IUS might go through (perforate) the womb or cervix when it is fitted. This may cause pain, but often there are no symptoms. If this happens, the IUS may have to be removed by surgery. Perforation is rare when an IUS is fitted by an experienced doctor or nurse.

How is an Intrauterine System used?

An IUS has to be put in and removed by a specially trained doctor or nurse. It is put in either towards the end of your period or a few days after. The doctor or nurse must make sure there is no chance of you being pregnant before they fit an IUS. You will be examined internally to find the position and size of your womb before the IUS is fitted. It can be uncomfortable having an IUS fitted and you might want to have a painkiller or a local anaesthetic. Talk to your doctor or nurse about this beforehand. You may get a period-type pain and some bleeding for a few days after the IUS is fitted. Painkillers can help with this.

What to watch out for with an Intrauterine System?

An IUS has threads attached to the end which hang a little way down from your womb into the top of your vagina. The doctor or nurse will teach you to feel for the threads to make sure the IUS is still in place. You should do this regularly in the first month and then after each period or at regular intervals. It is very unlikely that an IUS will fall out, but if you cannot feel the threads or if you think you can feel the IUS itself, you should see your doctor or nurse straight away. In the meantime, use an extra contraceptive method, such as condoms. Rarely, your partner may say he can feel the threads during sex. If this is the case, get your doctor or nurse to check the threads and either move them out of the way or shorten them. If you feel unwell and have any pain in your lower abdomen, with a high temperature or a smelly discharge from your vagina in the first three weeks after the IUS is fitted, see a doctor or go back to the family planning clinic as soon as possible. This is because you may have an infection. You need to have your IUS checked by a doctor or nurse four to six weeks after it is put in, and then once a year. The IUS can stay in for five years. Contact your doctor or nurse if you have any problems between regular visits.

A trained doctor or nurse can take out the IUS at any time. If you are not going to have another IUS put in, and you don't want to become pregnant, you will need to use an extra contraceptive method, such as condoms, for seven days before the IUS is taken out. This is to stop sperm getting into your body. Sperm can live for up to seven days inside your body, and could fertilise an egg once the IUS is removed. Your usual periods and fertility return quickly after removing the IUS. Most women find that after the first few months, their periods become lighter than usual. Some women may find that their periods stop altogether. If this happens to you, do not worry as it is perfectly healthy. When the IUS is taken out your periods will return to how they were before it was put in. It is very rare to get pregnant with the IUS, but if you miss a period and are worried that you might be pregnant you should see a doctor or nurse as soon as possible. If you are pregnant your doctor will need to discuss the situation with you and take out the IUS.

Can anything make an Intrauterine System less effective?

Once an IUS has been put into your womb you are protected from getting pregnant unless the IUS is removed or comes out.