Long Acting Reversible Contraception

The contraceptive injection

A woman can get pregnant if a man’s sperm reaches one of her eggs (ova). Contraception tries to stop this happening by keeping the egg and sperm apart or by stopping egg production. One method of contraception is the injection.

We offer the Depo-Provera injection, which lasts for 12 weeks. The most popular is Depo-Provera.

The injection contains progestogen. This thickens the mucus in the cervix, stopping sperm reaching an egg. It also thins the womb lining and, in some, prevents the release of an egg.

At a glance: the contraceptive injection

If used correctly the contraceptive injection is more than 99% effective. This means that less than one woman in 100 who use the injection will become pregnant in a year.

The injection we offer lasts for 12 weeks, so you dont have to think about contraception every day or every time you have sex.

It can be useful for women who might forget to take the contraceptive pill every day.

It can be useful for women who cant use contraception that contains oestrogen.

Its not affected by medication.

The contraceptive injection may provide some protection against cancer of the womb and pelvic inflammatory disease.

Side effects can include weight gain, headaches, mood swings, breast tenderness and irregular bleeding. The injection cant be removed from your body, so if you have side effects theyll last as long as the injection and for some time afterwards.

Your periods may become more irregular or longer, or stop altogether (amenorrhoea). Treatment is available if your bleeding is heavy or longer than normal – talk to your doctor or nurse about this.

It can take up to one year for your fertility to return to normal after the injection wears off, so it may not be suitable if you want to have a baby in the near future.

Using Depo-Provera affects your natural oestrogen levels, which can cause thinning of the bones.

The injection does not protect against sexually transmitted infections (STIs). By using condoms as well as the injection, youll help to protect yourself against STIs.

How the injection works

The contraceptive injection is usually given into a muscle in your bottom, although sometimes it may be given in a muscle in your upper arm. The contraceptive injection works in the same way as the implant. It steadily releases the hormone progestogen into your bloodstream. Progestogen is similar to the natural hormone progesterone, which is released by a womans ovaries during her period.

The continuous release of progestogen:

  • stops a woman releasing an egg every month (ovulation)
  • thickens the mucus from the cervix (neck of the womb), making it difficult for sperm to pass through to the womb and reach an unfertilised egg
  • makes the lining of the womb thinner so that it is unable to support a fertilised egg

The injection can be given at any time during your menstrual cycle, as long as you and your doctor are reasonably sure you are not pregnant.

When it starts to work

If you have the injection during the first five days of your cycle, you will be immediately protected against becoming pregnant.

If you have the injection on any other day of your cycle, you will not be protected against pregnancy for up to seven days. Use condoms or another method of contraception during this time.

After giving birth

You can have the contraceptive injection at any time after you have given birth, if you are not breastfeeding. If you are breastfeeding, the injection will usually be given after six weeks, although it may be given earlier if necessary.

If you start injections on or before day 21 after giving birth, you will be immediately protected against becoming pregnant.

If you start injections after day 21, you will need to use additional contraception for the following seven days.

Heavy and irregular bleeding is more likely to occur if you have the contraceptive injection during the first few weeks after giving birth.

It is safe to use contraceptive injections while you are breastfeeding.

After a miscarriage or abortion

You can have the injection immediately after a miscarriage or abortion, and you will be protected against pregnancy straight away. If you have the injection more than five days after a miscarriage or abortion, youll need to use additional contraception for seven days.

Who can use the injection?

Most women can be given the contraceptive injection. It may not be suitable if you:

  • think you might be pregnant
  • want to keep having regular periods
  • have bleeding in between periods or after sex
  • have arterial disease or a history of heart disease or stroke
  • have a blood clot in a blood vessel (thrombosis)
  • have liver disease
  • have migraines
  • have breast cancer or have had it in the past
  • have diabetes with complications
  • have cirrhosis or liver tumours
  • are at risk of osteoporosis

Advantages and disadvantages of the injection

The main advantages of the contraceptive injection are:

  • each injection lasts for either eight or 12 weeks
  • the injection does not interrupt sex
  • the injection is an option if you cannot use oestrogen-based contraception, such as the combined pill, contraceptive patch or vaginal ring
  • you do not have to remember to take a pill every day
  • the injection is safe to use while you are breastfeeding
  • the injection is not affected by other medicines
  • the injection may reduce heavy, painful periods and help with premenstrual symptoms for some women
  • the injection offers some protection from pelvic inflammatory disease (the mucus from the cervix may stop bacteria entering the womb) and may also give some protection against cancer of the womb

Using the contraceptive injection may have some disadvantages, which you should consider carefully before deciding on the right method of contraception for you. These are as follows.

Disrupted periods

Your periods may change significantly during the first year of using the injection. They will usually become irregular and may be very heavy, or shorter and lighter, or stop altogether. This may settle down after the first year, but may continue as long as the injected progestogen remains in your body.

It can take a while for your periods and natural fertility to return after you stop using the injection. It takes around eight to 12 weeks for injected progestogen to leave the body, but you may have to wait longer for your periods to return to normal if you are trying to get pregnant.

Until you are ovulating regularly each month, it can be difficult to work out when you are at your most fertile. In some cases, it can take three months to a year for your periods to return to normal.

Weight gain

You may put on weight when you use contraceptive injections, although some women lose weight. Use of the injections may be associated with an increase in weight of up to 2–3kg over one year.

Depo-Provera, oestrogen and bone risk

Using Depo-Provera affects your natural oestrogen levels, which can cause thinning of the bones but it does not increase your risk of bone fracture (breaking a bone). This isnt a problem for most women because the bone replaces itself when you stop the injection, and it doesnt appear to cause any long-term problems.

Thinning of the bones may be a problem for women who already have an increased risk of developing osteoporosis (for example because they have low oestrogen, or a family history of osteoporosis). It may also be a concern for women under 19 because the body is still making bone at this age. Women under 19 may use Depo-Provera, but only after careful evaluation by a doctor.

Other side effects that some women report are:

  • headaches
  • acne
  • tender breasts
  • changes in mood
  • loss of sex drive

Will other medicines affect the injection?

No – the contraceptive injection is not affected by other medication.

Risks

There is a small risk of infection at the site of the injection. In very rare cases, some people may have an allergic reaction to the injection.

Where you can get it

Most types of contraception are available free in the UK. Contraception is free to all women and men through the NHS. You can get contraception at:

  • most GP surgeries – talk to your GP or practice nurse
  • community contraception clinics
  • some genitourinary medicine (GUM) clinics
  • sexual health clinics – they also offer contraceptive and STI testing services
  • some young people’s services (call 0800 567 123 for more information)

Find your nearest sexual health clinic by searching by postcode or town.

Contraception services are free and confidential, including for people under the age of 16.

If youre under 16 and want contraception, the doctor, nurse or pharmacist wont tell your parents (or carer) as long as they believe you fully understand the information youre given, and your decisions. Doctors and nurses work under strict guidelines when dealing with people under 16.

Theyll encourage you to consider telling your parents, but they wont make you. The only time that a professional might want to tell someone else is if they believe youre at risk of harm, such as abuse. The risk would need to be serious, and they would usually discuss this with you first.

Find out more about the medicines used in the contraceptive injection.

Contraceptive Implant

A woman can get pregnant if a man’s sperm reaches one of her eggs (ova). Contraception tries to stop this happening by keeping the egg and sperm apart or by stopping egg production. One method is the implant.

The contraceptive implant is a small flexible tube about 40mm long thats inserted under the skin of your upper arm. Its inserted by a trained professional, such as a doctor, and lasts for three years.

The implant stops the release of an egg from the ovary by slowly releasing progestogen into your body. Progestogen thickens the cervical mucus and thins the womb lining. This makes it harder for sperm to move through your cervix, and less likely for your womb to accept a fertilised egg.

At a glance: the implant

If implanted correctly, its more than 99% effective. Fewer than one woman in 1,000 who use the implant as contraception will get pregnant in one year.

Its very useful for women who know they dont want to get pregnant for a while. Once the implant is in place, you dont have to think about contraception for three years.

It can be useful for women who cant use contraception that contains oestrogen.

Its very useful for women who find it difficult to take a pill at the same time every day.

If you have side effects, the implant can be taken out. However, whilst you can have the implant removed at any time, we recommend keeping it in for one year and managing any side effects that occur prior to removal.

When its first put in, you may feel some bruising, tenderness or swelling around the implant.

In the first year after the implant is fitted, your periods may become irregular, lighter, heavier or longer. This usually settles down after the first year.

A common side effect of the implant is that your periods stop (amenorrhoea). Its not harmful, but you may want to consider this before deciding to have an implant.

Some medications can make the implant less effective, and additional contraceptive precautions need to be followed when you are taking these medications (see Will other medicines affect the implant?).

The implant does not protect against sexually transmitted infections (STIs). By using condoms as well as the implant, youll help to protect yourself against STIs.

How the implant works

The implant steadily releases the hormone progestogen into your bloodstream. Progestogen is similar to the natural hormone progesterone, which is released by a womans ovaries during her period.

  • The continuous release of progestogen:
  • stops a woman releasing an egg every month (ovulation)
  • thickens the mucus from the cervix (entrance to the womb), making it difficult for sperm to pass through to the womb and reach an unfertilised egg
  • makes the lining of the womb thinner so that it is unable to support a fertilised egg

The implant can be put in at any time during your menstrual cycle, as long as you and your doctor are reasonably sure you are not pregnant. In the UK, Nexplanon is the main contraceptive implant currently in use. Implants inserted before October 2010 were called Implanon. Since October 2010 insertion of Implanon has decreased as stocks are used up, and Nexplanon has become the most commonly used implant.

Both types of implant work in the same way, but Nexplanon is designed to reduce the risk of insertion errors and is visible on an X-ray or CT (computerised tomography) scan. There is no need for existing Implanon users to have their implant removed and replaced by Nexplanon ahead of its usual replacement time.

Nexplanon is a small, thin, flexible tube about 4cm long. It is implanted under the skin of your upper arm by a doctor or nurse. A local anaesthetic is used to numb the area. The small wound made in your arm is closed with a dressing and does not need stitches.

Nexplanon works for up to three years before it needs to be replaced. You can continue to use it until you reach the menopause, when a woman’s monthly periods stop at around 52 years of age. However, whilst you can have the implant removed at any time, we recommend keeping it in for one year and managing any side effects that occur prior to removal. If you do choose to remove the implant it only takes a few minutes to remove, using a local anaesthetic.

As soon as the implant has been removed, you will no longer be protected against pregnancy.

When it starts to work

If the implant is fitted during the first five days of your menstrual cycle, you will be immediately protected against becoming pregnant. If it is fitted on any other day of your menstrual cycle, you will not be protected against pregnancy for up to seven days, and should use another method, such as condoms.  

After giving birth

You can have the contraceptive implant fitted after you have given birth, usually after three weeks.

If it is fitted on or before day 21 after the birth, you will be immediately protected against becoming pregnant.

If it is fitted after day 21, you will need to use additional contraception, such as condoms, for the following seven days.

It is safe to use the implant while you are breastfeeding.

After a miscarriage or abortion

The implant can be fitted immediately after a miscarriage or an abortion, and you will be protected against pregnancy straight away.

Who can use the implant

Most women can be fitted with the contraceptive implant. It may not be suitable if you:

  • think you might be pregnant
  • want to keep having regular periods
  • have bleeding in between periods or after sex
  • have arterial disease or a history of heart disease or stroke
  • have a blood clot in a blood vessel (thrombosis)
  • have liver disease
  • have migraines
  • have breast cancer or have had it in the past
  • have diabetes with complications
  • have cirrhosis or liver tumours
  • are at risk of osteoporosis

Advantages and disadvantages of the implant

The main advantages of the contraceptive implant are:

  • it works for three years
  • the implant does not interrupt sex
  • it is an option if you cannot use oestrogen-based contraception, such as the combined contraceptive pill, contraceptive patch or vaginal ring
  • you do not have to remember to take a pill every day
  • the implant is safe to use while you are breastfeeding
  • your fertility should return to normal as soon as the implant is removed
  • implants offer some protection against pelvic inflammatory disease (the mucus from the cervix may stop bacteria entering the womb) and may also give some protection against cancer of the womb
  • the implant may reduce heavy periods or painful periods after the first year of use
  • after the contraceptive implant has been inserted, you should be able to carry out normal activities

Using a contraceptive implant may have some disadvantages, which you should consider carefully before deciding on the right method of contraception for you. These include:

Disrupted periods

Your periods may change significantly while using a contraceptive implant. Around 20% of women using the implant will have no bleeding, and almost 50% will have infrequent or prolonged bleeding. Bleeding patterns are likely to remain irregular, although they may settle down after the first year.

Although these changes are not harmful, they may not be acceptable for some women. Your GP may be able to help by providing additional medication if you have prolonged bleeding.

Other side effects that some women report are:

  • headaches
  • acne
  • nausea
  • breast tenderness
  • changes in mood
  • loss of sex drive

These side effects usually stop after the first few months. If you have prolonged or severe headaches or other side effects, tell your doctor.

Some women put on weight while using the implant, but there is no evidence to show that the implant causes weight gain.

Will other medicines affect the implant?

Some medicines can reduce the implants effectiveness. These include:

  • medication for HIV
  • medication for epilepsy
  • complementary remedies, such as St Johns Wort
  • an antibiotic called rifabutin (which can be used to treat tuberculosis)
  • an antibiotic called rifampicin (which can be used to treat several conditions, including tuberculosis and meningitis)

These are called enzyme inducing drugs. If you are using these medicines for a short while (for example, rifampicin to protect against meningitis), it is recommended that you use additional contraception during the course of treatment and for 28 days afterwards. The additional contraception could be condoms, or a single dose of the contraceptive injection. The implant can remain in place if you have the injection.

Women taking enzyme inducing drugs in the long term may wish to consider using a method of contraception that isnt affected by their medication.

Always tell your doctor that you are using an implant if you are prescribed any medicines. Ask your doctor or nurse for more details about the implant and other medication.

Risks of the implant

In rare cases, the area of skin where the implant has been fitted can become infected. If this happens, the area will be cleaned and may be treated with antibiotics.

Where you can get the contraceptive implant

Most types of contraception are available free in the UK. Contraception is free to all women and men through the NHS. Places where you can get contraception include:

  • most GP surgeries – talk to your GP or practice nurse
  • community contraception clinics
  • some genitourinary medicine (GUM) clinics
  • sexual health clinics – they also offer contraceptive and STI testing services
  • some young people’s services (call 0800 567 123 for more information)

Find your nearest sexual health clinic by searching by postcode or town.

Contraception services are free and confidential, including for people under the age of 16.

If youre under 16 and want contraception, the doctor, nurse or pharmacist wont tell your parents (or carer) as long as they believe you fully understand the information youre given, and your decisions. Doctors and nurses work under strict guidelines when dealing with people under 16. Theyll encourage you to consider telling your parents, but they wont make you. The only time that a professional might want to tell someone else is if they believe youre at risk of harm, such as abuse. The risk would need to be serious, and they would usually discuss this with you first.

The intrauterine device (IUD)

At a glance: the intrauterine device (IUD)

Find everything you need to know about the intrauterine device (IUD), including when it is used, how it is fitted, and the risks. Plus links to other useful resources.

An intrauterine device (IUD) is a small, T-shaped contraceptive device made from plastic and copper that fits inside the womb (uterus). It used to be called a coil or a loop.

It’s a long-lasting and reversible method of contraception but it is not a barrier method. This means that an IUD can prevent pregnancy but won’t stop you getting sexually transmitted infections (STIs). It’s different to an intrauterine system (IUS) which releases the hormone progestogen into the body.

An IUD stops sperm from reaching the egg. It does this by releasing copper, which changes the make-up of the fluids in the womb and fallopian tubes. These changes prevent sperm from fertilising eggs. IUDs may also stop fertilised eggs from travelling along the fallopian tubes and implanting in the womb.

How do I get an IUD fitted?

There are different types and sizes of IUD to suit different women. IUDs need to be fitted by a trained doctor or nurse at your GP surgery, local family planning clinic or sexual health clinic. You may need to be tested for infection before the fitting or you may be given antibiotics, in case of infection, to take as it’s fitted.

It takes about 15 to 20 minutes to insert an IUD. The vagina is held open, like it is during a cervical smear test, and the IUD is inserted through the cervix and into the womb.

Some women find having an IUD fitted uncomfortable and painful, so you may also be offered painkillers. Read more about having an IUD fitted.

An IUD can stay in the womb for five to 10 years depending on the type. If you’re 40 or over when you have an IUD fitted, it can be left in until you reach the menopause or until you no longer need contraception.

Most women can have an IUD fitted, including women who have never been pregnant or who are HIV positive. An IUD is usually fitted during your menstrual period. From the moment the IUD is fitted until the time it is taken out, you are protected against pregnancy.

Read more information on when an IUD can be used.

Removing an IUD

An IUD can be removed at any time by a trained doctor or nurse. However, whilst you can have the implant removed at any time, we recommend keeping it in for one year and managing any side effects that occur prior to removal.

If you’re not going to have another IUD put in and you don’t want to become pregnant, use another contraceptive method (such as condoms) for seven days before you have the IUD removed. This is to stop sperm getting into your body. Sperm can live for seven days in the body and could cause pregnancy once the IUD is removed.

As soon as an IUD is taken out, your normal fertility should return.

How effective is an IUD?

An IUD is 98–99% effective at preventing pregnancy. Newer models that contain more copper are the most effective (over 99% effective). This means that less than one in every 100 women who use the IUD will get pregnant in a year.

As a long-lasting method of contraception, the IUD is very effective. You don’t need to remember to take or use contraception to prevent pregnancy. However, there are some disadvantages to an IUD, such as longer and more painful periods. And you’ll still need to use other types of contraception to prevent STIs. Read more about the things to consider before getting an IUD.

In rare cases there may also be some complications after having an IUD fitted. This can include pelvic infections in the first 20 days after fitting, or the IUD moving out of place. Read more about the risks of having an IUD fitted.

Emergency contraception

The IUD can also be used as a method of emergency contraception up to five days after unprotected sex or up to five days after the earliest time you could have released an egg (ovulation). If you have unprotected sex, make an appointment with your GP or clinic as soon as possible.

Who can use an IUD

Find out who can use an IUD. Most women can use an IUD, including women who have never been pregnant and those who are HIV positive.

Most women can use an IUD, including women who have never been pregnant and those who are HIV positive. Your GP or clinician will ask about your medical history to check if an IUD is the most suitable form of contraception for you.

You should not use an IUD if you have:

Women who have had an ectopic pregnancy or recent abortion, or who have an artificial heart valve, must consult their GP or clinician before having an IUD fitted.

You should not be fitted with an IUD if there’s a chance that you are already pregnant or if you or your partner are at risk of catching STIs.

The IUD is most appropriate for women with one long-term partner, who they’re confident doesn’t have any STIs. If you or your partner are unsure, go to your GP or sexual health clinic to be tested for STIs.

Using an IUD after giving birth

An IUD can usually be fitted four to six weeks after giving birth (vaginal or caesarean). You’ll need to use alternative contraception from three weeks (21 days) after the birth until the IUD is fitted. In some cases, an IUD can be fitted within 48 hours of giving birth.

An IUD is safe to use when you’re breastfeeding and it won’t affect your milk supply.

Using an IUD after a miscarriage or abortion

An IUD can be fitted after an abortion or miscarriage by an experienced doctor or nurse, as long as you were pregnant for less than 24 weeks. If you were pregnant for more than 24 weeks, you may have to wait a few weeks before having an IUD fitted.

Having an IUD fitted

Learn about how an IUD is fitted, and the checks you must have beforehand, including an examination of your womb and an STI test.

Your GP or clinician can advise you, based on your medical history, whether an IUD is the best method of contraception for you.

Before you have an IUD fitted, you will have an internal examination to determine the size and position of your womb. This is to make sure that the IUD can be positioned in the correct place.

You may also be tested for infection, such as sexually transmitted infections (STIs). It’s best to do this before an IUD is fitted so that any infections can be treated. Sometimes, you may be given antibiotics at the same time as the IUD is fitted.

It takes about 15 to 20 minutes to insert an IUD. The vagina is held open, like it is during a cervical smear test, and the IUD is inserted through the cervix and into the womb.

The fitting process can be uncomfortable and sometimes painful. You may experience cramps afterwards.

You can ask for a local anaesthetic or painkillers, such as ibuprofen, before having the IUD fitted. Discuss this with your GP or clinician beforehand. An anaesthetic injection itself can be painful, so many women have the procedure without one.

You may get period-like pain and bleeding for a few days after having an IUD fitted. This is normal. Painkillers before and after the procedure can ease this.

Check-ups

Once an IUD is fitted, it will need to be checked by a doctor after three to six weeks. Speak to your GP or clinician if you have any problems after this initial check or if you want the device removed.

Also speak to your GP or clinician if you or your partner are at risk of getting an STI. This is because STIs can lead to an infection in the pelvis.

Feeling unwell after having an IUD fitted

If you feel unwell, have pain in your lower abdomen, have a high temperature or a smelly discharge after having an IUD fitted, see your GP or go back to the clinic where it was fitted as soon as you can. You may have an infection.

How to tell whether an IUD is still in place

Once fitted, an IUD has two thin threads that hang down a little way from your womb into the top of your vagina. The GP or clinician who fits your IUD will teach you how to feel for these threads and check that the IUD is still in place.

Check your IUD is in place a few times in the first month after fitting, and then after each period or at regular intervals.

It’s very unlikely that your IUD will come out, but if you can’t feel the threads or if you think the IUD has moved, you may not be fully protected against pregnancy. See your GP or clinician straight away and use extra contraception until your IUD has been checked. If you’ve had sex recently, you may need to use emergency contraception.

Sex

Your partner shouldn’t be able to feel your IUD during sex. If he can feel the threads, get your GP or nurse to check that your IUD is in place. If you feel any pain during sexual intercourse, go for a check-up with your GP or clinician.

Things to consider

Although an IUD is an effective method of contraception, there are a number of things to consider before having one fitted.

Although an IUD is an effective method of contraception, there are some things to consider before having one fitted.

Advantages of an IUD

  • Most women can use an IUD, including women who have never been pregnant.
  • Once an IUD is fitted, it is immediately effective at preventing pregnancy for up to 10 years or until it’s removed.
  • It doesn’t interrupt sex.
  • It can be used if you’re breastfeeding.
  • Your normal fertility returns as soon as the IUD is taken out.
  • It’s not affected by other medicines.

There’s no evidence that having an IUD fitted will increase the risk of cancer of the cervix, endometrium (lining of the womb) or ovaries. Some women experience changes in mood and libido, but these are very small.

Disadvantages of an IUD

  • Your periods may become heavier, longer or more painful, though this may improve after a few months.
  • You must have an internal examination to check whether an IUD is suitable for you, and another examination when it is fitted.
  • An IUD doesn’t protect against sexually transmitted infections (STIs), so you may have to use condoms as well. If you get an STI while you have an IUD fitted, it could lead to a pelvic infection if left untreated.

The most common reasons that women stop using an IUD are vaginal bleeding and pain.

Risks

Learn about complications after having an IUD fitted. Complications are rare, and most of them appear within the first year after fitting.

Complications after having an IUD fitted are rare. Most complications will appear within the first year after fitting.

Periods

Longer or heavier periods can be a side effect of the IUD (particularly if you’ve always had heavy periods). For some people, this eases within a few months, but others continue to have longer and heavier periods.

If the problems continue, you may wish to consider an intrauterine system (IUS), which releases hormones that can reduce bleeding and pain.

The most common reasons for women having their IUD removed are vaginal pain and bleeding.

Pelvic infections

Pelvic infections can occur in the first 20 days after the IUD is fitted. The risk of infection from an IUD is extremely small. Less than one in 100 women who are at low risk of sexually transmitted infections (STIs) will get a pelvic infection.

Your GP or clinician will usually recommend an internal examination before fitting an IUD to check that there are no existing infections.

See your GP or clinician immediately if you get any pain in your lower abdomen or have a high temperature or smelly discharge in the first three weeks after your IUD is fitted. This may be pelvic inflammatory disease (PID), which can lead toinfertility.

Rejection

Occasionally the IUD is rejected by the womb (expulsion) or can move (displacement). This is more likely to happen soon after it has been fitted, although this isn’t common. Your GP or clinician will teach you how to check that your IUD is in place.

Damage to the womb

In very rare cases, an IUD can go through (perforate) the womb or neck of the womb (cervix) when it’s put in. This can cause pain in the lower abdomen but doesn’t usually cause any other symptoms. If the GP or clinician fitting your IUD is experienced, the risk of this happening is extremely low.

If perforation occurs, you may need surgery to remove the IUD. Contact your GP immediately if you feel a lot of pain after having an IUD fitted as perforations should be treated straight away.

Ectopic pregnancy

If the contraception fails and you become pregnant, your IUD should be removed as soon as possible if you’re continuing with the pregnancy.

There’s a small increased risk of ectopic pregnancy if a woman becomes pregnant while using an IUD.

The intrauterine system (IUS)

At a glance: the intrauterine system (IUS)

Find everything you need to know about the intrauterine system (IUS), including when it is used, how it is fitted, and the possible complications.

An intrauterine system (IUS) is a small, T-shaped contraceptive device that fits inside the womb (uterus) and releases the female hormone progestogen into the body.

An IUS is a long-lasting and reversible method of contraception, but it is not a barrier method. This means that it cannot stop you getting sexually transmitted infections (STIs).

The IUS is similar to the intrauterine device (IUD), but works in a slightly different way. Rather than releasing copper like the IUD, the IUS releases the hormone progestogen, which is similar to the natural hormone progesterone that’s produced in a woman’s ovaries. This prevents pregnancy by stopping fertilised eggs from becoming embedded in the womb.

It does this by causing the womb lining to become thinner and less likely to accept a fertilised egg. It also thickens the mucus from the cervix (opening of the womb), making it harder for sperm to move through it and reach an egg. In some women, the IUS also stops the ovaries from releasing an egg (ovulation), but most women will continue to ovulate.

The IUS that’s available in the UK is called Mirena. It works for up to five years after being fitted. If you’re 45 or older when you have the IUS fitted, it can be left until you reach menopause or you no longer need contraception.

How do I get an IUS fitted?

Before fitting the IUS, your GP or clinician will perform an internal examination to check the position of the womb. You may also be tested for infection and offeredantibiotics.

It takes about 15 to 20 minutes to insert an IUS. The vagina is held open, like it is during a cervical smear test, and the IUS is inserted through the cervix and into the womb.

Some women find the procedure uncomfortable and painful, so you may be offered painkillers. And you may feel some cramping afterwards, but this will pass.

Read more about having an IUS fitted.

Who can use an IUS?

Most women can have the IUS fitted, including women who have never been pregnant or who are HIV positive. It must be fitted by a trained doctor or nurse at your GP surgery, family planning clinic or sexual health clinic. An IUS may not be suitable if you’re already pregnant, have an untreated sexually transmitted infection or have problems with your uterus or cervix. Read more about when an IUS can be used.

If it is fitted in the first seven days of your menstrual cycle, the IUS protects against pregnancy immediately. If it is fitted at another time, another type of contraception has to be used for the first seven days.

Removing an IUS

Your IUS can be removed at any time by a trained doctor or nurse. However, whilst you can have the implant removed at any time, we recommend keeping it in for one year and managing any side effects that occur prior to removal.

If you’re not going to have another IUS put in and you don’t want to become pregnant, use another contraceptive method (such as condoms) for seven days before you have the IUS removed. Sperm can live for seven days in the body and could fertilise an egg once the IUS is removed.

As soon as an IUS is taken out, your normal fertility should return.

How effective is an IUS?

The IUS is more than 99% effective in preventing pregnancy. This means that less than one in every 100 women who use the IUS will get pregnant over five years.

The IUS is safe and effective as a long-lasting method of contraception. Once it’s in place you won’t have to remember to take or use contraception to prevent pregnancy. It can also make your periods lighter, shorter or even stop them completely after the first year. This may help women with heavy periods or painful periods.

However, there are some disadvantages to an IUS as some women will experienceheadachesbreast tenderness and acne. You will also need to use other types of contraception to prevent sexually transmitted infections (STIs). Read more about the things you should consider before getting an IUS.

In rare cases there may also be some complications after having an IUS fitted. This can include pelvic infections in the first 20 days after fitting, or the IUD moving out of place and needing to be checked. Read more about the risks of having an IUS fitted.

Who can use an IUS

Find out when an IUS is used. Most women can use an IUS, including women who have never been pregnant and those who are HIV positive.

Most women can use an IUS, including women who have never been pregnant and those who are HIV positive. Your GP or clinician will ask about your medical history to check if an IUS is the most suitable form of contraception for you.

Your family and medical history will determine whether or not you can use an IUS. For example, this method of contraception may be unsuitable if you think you may already be pregnant or if you have:

Like the IUD, IUS can be unsuitable for women who have untreated STIs. A doctor will usually perform an internal examination to make sure you don’t have any existing infections.

Using an IUS after giving birth

An IUS can usually be fitted four to six weeks after giving birth (vaginal or caesarean). You’ll need to use alternative contraception from three weeks (21 days) after the birth until the IUS is put in. In some cases, an IUS can be fitted within 48 hours of giving birth.

It is safe to use an IUS when you’re breastfeeding and it won’t affect your milk supply.

Using an IUS after a miscarriage or abortion

An IUS can be fitted by an experienced doctor or nurse straight after an abortionor miscarriage, as long as you were pregnant for less than 24 weeks. If you were pregnant for more than 24 weeks, you may have to wait a few weeks before an IUS can be fitted.

Having an IUS fitted

Find out what happens when you have an IUS fitted. Beforehand, you will have an internal examination to make sure that the IUS can be positioned in the correct place.

Before you have an IUS fitted, you will have an internal examination to determine the size and position of your womb. This is to make sure that the IUS can be positioned in the correct place.

You may also be tested for any existing infections, such as sexually transmitted infections (STIs). It is best to do this before an IUS is fitted so that any infections can be treated. Sometimes, you may be given antibiotics at the same time as fitting an IUS.

It takes about 15 to 20 minutes to insert an IUS. The vagina is held open, like it is during a cervical smear test, and the IUS is inserted through the cervix and into the womb.

The fitting process can be uncomfortable and painful for some women, especially if you haven’t had children and your cervix isn’t stretched. You may also experience cramps afterwards.

You can ask for a local anaesthetic or painkillers, such as ibuprofen, before having the IUS fitted. Discuss this with your GP or nurse beforehand. An anaesthetic injection itself can be painful, so many women have the procedure without.

Irregular bleeding and spotting are common in the first six months after having an IUS fitted.

Check-ups

Once an IUS is fitted, it will need to be checked by a doctor after three to six weeks to make sure that everything is fine.

Speak to your GP or clinician if you have any problems after this initial check or if you want the device removed. Also speak to your GP if you or your partner are at risk of contracting an STI as this can lead infection in the pelvis.

Feeling unwell after having an IUS fitted

If you feel unwell, have pain in your lower abdomen, have a high temperature or a smelly discharge after having an IUS fitted, see your GP or go back to the clinic where it was fitted as soon as you can. You may have an infection.

How to tell if an IUS is still in place

Once it is fitted, an IUS has two thin threads that hang down a little way from your womb into the top of your vagina. The GP or clinician that fits your IUS will teach you how to feel for these threads and check that the IUS is still in place.

Check your IUS is in place a few times in the first month and then after each periodor at regular intervals.

It is very unlikely that your IUS will come out, but if you can’t feel the threads or if you think the IUS has moved, you may not be fully protected against pregnancy.

See your doctor or nurse straight away and use extra contraception until your IUS has been checked. If you’ve had sex recently, you may need to use emergency contraception.

Sex

Your partner shouldn’t be able to feel your IUS during sex. If he can feel the threads, get your GP or clinician to check that your IUS is in place. If you feel any pain during sexual intercourse, go for a check-up with your GP or clinician.

Things to consider

Although an IUS is an effective method of contraception, there are a number of things to take into consideration before having an IUS fitted.

Although an IUS is an effective method of contraception, there are a number of things to consider before having an IUS fitted.

Advantages of an IUS

  • It works for five years.
  • It’s one of the most effective forms of contraception available in the UK.
  • It doesn’t interrupt sex.
  • An IUS may be useful if you have heavy or painful periods because your periods usually become much lighter and shorter, and sometimes less painful. They may stop completely after the first year of use.
  • It can be used safely if you’re breastfeeding.
  • It’s not affected by other medicines.
  • It may be a good option if you can’t use oestrogens (hormones) such as those used in the combined contraceptive pill.
  • Your fertility will return to normal when the IUS is removed.

There’s no evidence that an IUS will affect body weight or that having an IUS fitted will increase the risk of cervical canceruterine cancer (lining of the womb) or ovarian cancer. Some women experience changes in mood and libido, but these are very small.

Disadvantages of an IUS

  • Some women won’t be happy with the way that their periods may change. For example, they may become lighter and more irregular or, in some cases, stop completely.
  • Some women experience headaches, acne and breast tenderness after having the IUS fitted.
  • An uncommon side effect of the IUS is the appearance of small fluid-filled cysts on the ovaries. These usually disappear without treatment.
  • An IUS doesn’t protect you against sexually transmitted infections (STIs) so you may also have to use condoms when having sex. If you get an STI while you have an IUS fitted, it could lead to pelvic infection if it’s not treated.

The most common reasons that women stop using an IUS are vaginal bleeding and pain, although this is uncommon. Hormonal problems can also occur but these are less common.

Risks

Complications caused by an IUS are rare and usually happen in the first six months after it has been fitted.

Complications caused by an IUS are rare and usually happen in the first six months after it has been fitted.

Pelvic infections

Pelvic infections may occur in the first 20 days after the IUS has been inserted.

The risk of infection from an IUS is extremely small (less than one in 100 in women who are at low risk of sexually transmitted infections (STIs). A GP or clinician will usually recommend an internal examination before fitting an IUS to be sure that there are no existing infections.

If you have any pain in your lower abdomen or have a high temperature or smelly discharge in the first three weeks after your IUS is fitted, see your GP or clinician immediately. This may be pelvic inflammatory disease (PID), which can lead to infertility.

Rejection

Occasionally, the IUS is rejected by the womb (expulsion) or it can move (displacement). This is not common and is more likely to happen soon after it has been fitted. Your doctor or nurse will teach you how to check that your IUS is in place.

Damage to the womb

In rare cases, an IUS can pierce the womb or neck of the womb (cervix) when it is put in. This can cause pain in the lower abdomen but doesn’t usually cause any other symptoms. If the doctor or nurse fitting your IUS is experienced, the risk of perforation is extremely low.

If perforation occurs, you may need surgery to remove the device. Contact your GP straight away if you feel a lot of pain after having an IUS fitted. Perforations should be treated immediately.

Ectopic pregnancy

If the contraception fails and you become pregnant, your IUS should be removed as soon as possible if you are continuing with the pregnancy. There’s a small increased risk of ectopic pregnancy if a woman becomes pregnant while using an IUS.

Family doctor Sarah Jarvis on the questions to ask

Read what family doctor Sarah Jarvis, a family doctor, would want to know if she was thinking of having an IUS fitted.

The IUS, known as the Mirena, is a more effective contraceptive than the combined contraceptive pill. Having the IUS fitted is a long-term solution to preventing pregnancy. It can also stop your periods, which is a huge advantage to many women.

We asked family doctor Sarah Jarvis what she would want to know if she was thinking of having an IUS fitted.

What’s the difference between an IUS and an IUD?
Both the intrauterine system (IUS) and intrauterine device (IUD) are T-shaped contraceptive devices, about one-and-a-half inches long, that are fitted inside the womb. An IUD (the coil) is made with copper and doesn’t contain any hormones. The IUS releases a tiny amount of the hormone progestogen into your womb. This stops the womb from sustaining a pregnancy.

Which is better for me?
Most women can have either fitted.

  • Women who haven’t had children usually prefer an IUD because the IUS is slightly larger.
  • If you like having regular periods because it reassures you, consider having an IUD fitted.
  • If you like the idea of having no periods, consider an IUS. An IUS can cause fairly irregular periods up to the first three to six months. But after a year, periods are more than 90% lighter and at least a third of women won’t have periods at all.

How effective is the IUS as a contraceptive?
About 99.9% (as effective as sterilisation) and completely reversible.

Where do I go to have an IUS fitted? 
It’s likely there will be a GP at your surgery who can fit one. Alternatively, phone your local family planning clinic and check whether they provide this service.

Does it hurt and can I feel it once it is inside?
Having an IUS fitted is slightly more uncomfortable than a smear test and takes a bit longer. Sometimes, the doctor will use local anaesthetic while fitting it. Once it is in, you will usually get some period-type cramps. These tend to settle down within two to three days. After that, most people don’t even know it is inside.

Will my partner be able to feel it during sex?
It’s highly unlikely. However, he may be able to feel the little wire threads that we leave outside the womb (so we can pull the IUS out). If that’s the case, when you go back for your IUS check-up, ask your GP if they can trim those threads. We like to keep them slightly longer for the first few weeks in case the womb pulls the device further up inside.

Can it ever fall out or dislodge?
It’s very unlikely that it will move, but it’s worth getting into the habit of putting a finger inside and checking you can still feel the threads. It occasionally falls out within the first few months of it being inserted, but after that, it is highly unlikely.

Can it cause any health problems, such as infections?
If you already have a low-grade infection, fitting an IUS can increase the chance of the infection going up into your womb and into your tubes. This can cause quite nasty problems. Your doctor or nurse will usually do some swab tests before you have the IUS fitted and will only fit it if your results are negative. Just having an IUS fitted shouldn’t cause infection.

Can I use tampons?
Absolutely, just as normal.

How long should I keep it in?
The IUS can be used for up to five years. If you have an IUS fitted after the age of 45 (or an IUD after the age of 40), you can keep it in until you have gone through the menopause, when you no longer need contraception.

Is it easily removed?
It is very easy to remove. It is much easier to remove than it is to put in, and it takes a few seconds. When we fit the IUS, we leave some little wire threads outside so we can just pull it out.

Will I be fertile as soon as it is removed?
Yes. As soon as it is taken out, your fertility returns immediately.

Can I have one fitted if I haven’t had children yet?
Yes. Some women find it slightly more uncomfortable to have fitted if they haven’t had children, and the IUS tends to be a little more uncomfortable than the IUD as it is slightly larger. But there’s no reason why you shouldn’t have one.

Will my periods be affected?
The IUS tends to cause irregular bleeding for the first three to six months, but after that your periods tail off. Some women don’t have periods at all after a year.

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