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Coils (intrauterine contraception)


A Coil is a small plastic T-shaped device which is placed inside your womb (uterus) to prevent you from getting pregnant.  It has one or two thin threads on the end that hang through your cervix (the entrance to the uterus) into the top of your vagina.  These threads cannot be felt and are not uncomfortable.

Once in place a coil can work for several years.  It can also be easily removed should you wish to become pregnant or change your contraceptive method.

Your fertility will return to normal as soon as the coil is removed.

A coil works by stopping sperm meeting the egg, which prevents fertilisation.  They may also work by preventing a fertilised egg from implanting into the womb.  Coils are over 99% effective and over 5yrs, less than 5 in 1000 people using a coil will become pregnant.  The coil is much more effective at preventing pregnancy than using pills or condoms. 

There are 2 types of coil; the copper coil and the hormone containing coil. 


The Copper coil – IUD (works for either 5 or 10yrs)

This coil works by stopping the sperm from fertilising the egg and preventing implantation.  It starts to work immediately after it is fitted and is effective for 5 or 10 years depending on which type of copper coil is inserted.

This coil does not contain any hormones and will not cause any hormonal side effects.  It will generally not change the regularity of your periods.  Some people may experience longer, heavier and more painful periods with this type of coil but this can settle over time. 

The copper coil can also be used for emergency contraception.

For more indepth information on the IUD (intrauterine device) or copper coil from the NHS website please click here


The Hormone containing coil (6yrs)

This type of coil is also known as the intrauterine system (IUS).  These coils contain a hormone called progestogen.  This hormone makes the lining of the womb thin so that an egg cannot implant.  It also makes the mucus at the neck of the womb thicker so sperm can’t get in.  After insertion it takes 7 days before the coil is effective and its contraceptive effect can last up to 5 or 6 years depending on type.

Because of the effect of progestogen on the lining of the womb (uterus) these coils can lead to changes in bleeding pattern.  Bleeding may become erratic and /or persistent in the beginning but this usually settles down over the first 3-6 months after insertion.  Once the bleeding has settled many people may have lighter, infrequent bleeding or they may have no bleeding at all.  Bleeding may also become less painful. 

A few people experience hormonal side effects such as acne, breast tenderness, headaches and mood changes.  These will also often settle with time.

These hormone containing coils can also be used to treat people with heavy painful periods and can also be used as part of Hormone Replacement Therapy.

Click here for more indepth information on the IUS (intrauterine system) or hormonal coil from the NHS website. 

The Sexual Health Service are unable to offer coil insertions to people who require a coil fit for non-contraceptive reasons.  For example: if you need a coil fitting for heavy periods or HRT but do not require it for contraception, or you or your partner has had a sterilisation/vasectomy procedure in the past, WE WILL BE UNABLE to provide this.  Please contact your GP to arrange the fitting elsewhere.

The coil can be fitted at any time if we can ensure that there is no risk that you could be pregnant.  This means that you must be using a reliable method of contraception in the month before your appointment e.g. the ‘pill’ taken correctly, condoms used correctly, the injection or the implant.  Withdrawal (the removal of a man’s penis from the vagina before he ejaculates) is NOT considered a reliable method.

If you are not using any of the reliable methods above or your current contraceptive method has expired then you MUST NOT have any unprotected sex from the first day of your period or for a minimum of 3 weeks before your appointment until after you are seen. 

If you have recently had a baby, you should start using reliable contraception 21 days after giving birth. You can have a coil fitted from 4 weeks after the birth in most cases.

If you have recently had a pregnancy loss or abortion you can have a coil inserted at any time provided, we can be certain you are not pregnant.

We may need to do a pregnancy test on the day of your appointment for confirmation.  If there is any concern that you could be pregnant, the coil will not be fitted. In this case, you may be offered an alternative method of contraception or asked to return at a later date to have the coil fitted

If you are suffering from heavy and/or unpredictable bleeding or you are having bleeding after sexual intercourse, then we may advise you to have other investigations prior to inserting the coil.  We will discuss this with at your appointment.


Emergency contraception – the copper coil

If you have had unprotected sexual intercourse and need advice, then please call us as soon as possible to discuss this.   We can provide emergency contraception, but this relies on seeing you as soon as possible after the episode of unprotected sexual intercourse. The copper coil can be used as a form of emergency contraception in many circumstances and can then be used as a reliable form of contraception.

Please call us on 0300 300 2016 asap.

If you would like your coil replaced, then please avoid having sex for 7 days before your appointment.  This is just in case we are unable to fit a new coil for you which would then mean you are at risk of a pregnancy.   

If your coil is overdue for removal/ renewal, please use an alternative contraception (or abstain from sexual intercourse) until your appointment. It is important to ensure that you abstain from sex or use additional precautions e.g. condoms for at least 21 days prior to your appointment.  We will then be able to carry out a reliable pregnancy test at your appointment. 

If you do not want another coil inserted at the time of removal but do not wish to become pregnant then you should consider alternative methods of contraception. For seamless contraception then you may want to start another form of contraception prior to your coil removal appointment. 

Please arrive 10 minutes before your appointment time.  If you are late then we may well not be able to see you.   

Please do not pass urine until you have been seen by the doctor, in case we need a sample.

Before we fit your coil, we will ask you about your general and sexual health and answer any questions you may have. We will offer you swab tests to check you for sexually transmitted infections (chlamydia and gonorrhoea) and a blood test to check for syphilis and HIV.

We will examine you to check which way your womb is lying and also to look at the neck of the womb (the cervix).  This is similar to when you have a smear test. You will have a health care support worker looking after you the whole time during the examination and fitting.

Some people may experience some mild abdominal discomfort, a bit like period pain, during the insertion procedure.  To help reduce this then you may like to take a dose of your usual painkiller (e.g. paracetamol or ibuprofen) 1 hour before your appointment. We also offer a local anaesthetic injections.

Occasionally people can feel a bit shaky after their appointment so it is helpful if there is someone who can take you home.  We would also advise you, if at all possible, NOT to bring children to your appointment with you.  

You should expect to be in the clinic for approximately 1 hour. 

  • Changes in bleeding pattern
    • It is common to experience irregular, prolonged or frequent bleeding especially in the first 3-6 months. Bleeding patterns should improve with time.
    • Infrequent or no bleeding can occur with the IUS (hormone containing coil)
  • Hormonal side effects (IUS only)
    • Some people may experience acne, breast tenderness, headaches or mood changes. These may also settle down over time.
  • Failure
    • The coil is a very effective form of contraception and only approximately 5 in 1000 people will fall pregnant with this method (compared with oral contraceptive pills which fail in 1 in 100 people).
  • Ectopic pregnancy
    • This is a pregnancy that occurs outside of the womb. In the unlikely event that a pregnancy does occur with a coil in place then up to 50% of these pregnancies may be ectopic. 
    • You are much less likely to have an ectopic pregnancy while you’re using a coil then if you are not using any contraception.
  • Expulsion
    • In 1 in 20 people the coil can be pushed out (expulsion) by your uterus (womb) or it can move (displacement). This isn’t common.
    • It’s more likely to happen soon after the coil has been put in and you may not know that it’s happened.
    • Your doctor or nurse will teach you how to check the threads so that you know the coil is in place.
  • Perforation
    • There is a very small risk that the coil might go through (perforate) your uterus or cervix when it is put in (up to 2 in 1000 insertions).
    • This risk is higher in people who are breastfeeding (up to 12 in 1000 insertions).
    • This may cause pain but often there are no symptoms and the uterus or cervix will heal by itself.
    • The risk of perforation is low when a coil is fitted by an experienced clinician.
    • If it does happen, the coil may have to be removed by surgery.
  • Infection
    • There is a small risk of infection after having your coil fitted. This risk is highest in the first 3 weeks after your coil is fitted but can occur anytime whilst the coil is in. 
    • Signs to look out for are pain that doesn’t settle, pain during sex, a change in or increased discharge and generally feeling unwell.
    • Pelvic infections are rare, but it is important you seek medical attention if you have any of these symptoms for review and prompt treatment with antibiotics.
    • You may be advised to have a check for sexually transmitted infections (STIs) before a coil is fitted or at the time it is fitted.

Please remember that the coil does not protect you against sexually transmitted infections.  We would advise you to use a condom with any new partner until you have both been tested.  If you would like a check for sexually transmitted infections before your coil fit, you can order a testing kit to be posted to you through our website.  Please allow 2 weeks for the results to be available. 

It is important that you have read and understood the information provided above before your coil insertion with us so that we can make the procedure as simple and efficient as possible.  We will only be able to fit the coil on the day if we feel it is safe to do so. 

We will be unable to routinely fit the coil if there is any risk of pregnancy at the time of the appointment.  (This does not apply if you are attending for emergency contraception for which you have already been counselled for.)  Please use a reliable form of contraception until after the coil is fitted or abstain from sexual intercourse from the first day of your period or for 3 weeks before the appointment date. 

If you have any concerns about a possible risk then please contact us as soon as you can before your appointment to discuss this.

If you are attending for a coil replacement then you should not have sex for 7 days prior to the appointment to avoid the risk of unwanted pregnancy.


Making a Booking

Book your appointment by calling 0300 300 2016.

If you need emergency contraception please call us for advice as soon as possible



We understand that for some people English is not their first language and they may have difficulty understanding discussions with detailed medical information.  We can arrange for an independent interpreter to attend your appointment or be available via the telephone at your appointment time.

If you would like to have an interpreter, please phone us to arrange your appointment and interpreter on 0300 300 2016.  In this case we will not be able to offer you an appointment at that time,  but someone will call you back to arrange the appointment, once they have managed to arrange an interpreter.


After your coil fitting

Keep a note of the expiry date of your coil as we will not contact you to remind you when it is due to be replaced. 

It is not unusual for some people to experience cramping or bleeding after having their coil fitted.  If you are experiencing any problems after having your coil fitted then please watch this video, which covers the most frequently asked questions following a coil insertion.


(Solent Sexual health would like to thank Sandyford Sexual Health Service for the use of this video)

If you still need advice then please do not hesitate to contact us or your GP.  If it is out of hours and urgent then contact 111 unless you feel it is an emergency in which case please attend your local A&E.

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