Contraception

What is a coil?

An intrauterine device (IUD), also known as a coil, is a device that is inserted into the womb to prevent pregnancy. It is T-shaped and slightly smaller than a hair grip.

Two types of IUDs are currently available:

1) The hormone intrauterine system (IUS) – Mirena® or Jaydess®: Both contain slow-release progesterone hormone. The Jaydess coil is effective for 3 years. The Mirena coil is effective for 5 years and, as well as preventing pregnancy, can also be used to help with heavy menstrual bleeding or as part of HRT.

2) The copper IUD: This releases copper in the womb and is effective for either 5 or 10 years.

How does a coil work?

The hormone IUS works by thickening the mucous plug in the neck of the womb (cervix). This stops sperm getting through to the womb to fertilise an egg. It also thins the womb lining to make it unlikely that a fertilised egg would be able to implant there. The effect of this is to make your periods lighter or non-existent. In some women, it suppresses egg release (ovulation) too.

The copper IUD works by releasing copper ions into the womb which are toxic to sperm and stops the sperm from surviving. It also prevents a fertilised egg from implanting onto the wall of the womb. Periods and ovulation continue as normal.

Neither option will protect from sexually transmitted infections.

 

How well does the coil work?

Both the hormone IUS and the copper IUD are very effective. For every 100 women with a IUD, fewer than 1 per year will become pregnant. However, if pregnancy does occur, there is an increased risk of that pregnancy being ectopic (a pregnancy that does not occur in the womb).

Are there any risks?

• PERFORATION OF THE UTERUS – This is a rare situation where the IUD makes a small hole in the womb and can escape into the pelvis. This happens in fewer than 2 women per 1000 insertions (it is approximately six times higher in breastfeeding women). It can cause pain, but not always. The main symptom is not being able to feel the coil threads. If a perforation occurs the coil usually needs to be retrieved by abdominal surgery. If you cannot feel the coil threads make an appointment to see your doctor.
• ECTOPIC PREGNANCY – The risk of pregnancy is small but if it occurs there is an increased risk of the pregnancy being ectopic. See a doctor urgently if you develop lower, one-sided tummy (abdominal) pain.
• EXPULSION – The risk of the IUD being pushed out of the womb through the cervix (expelled) is around 1 in 20 and is most common in the first three months after fitting. It is slightly more likely to happen if you have not had children or if the fitting was particularly uncomfortable. If you cannot feel the threads of the coil, make an appointment to see your doctor.
• INFECTION – There is a six times increase in the risk of infection in the first 20 days following insertion. If you develop heavy bleeding, vaginal discharge or pelvic pain you must see your doctor. The risk of infection is reduced if intercourse is avoided for 48 hours after insertion (this allows the protective plug of mucous at the cervix to reform).
• FAILURE TO FIT – Sometimes it is not possible to fit the coil in the surgery. This does not happen commonly but reasons for this include: an unusual shape of the womb or the presence of fibroids in the womb, the womb being too small for the coil, the neck of the womb being too narrow to pass the coil through or the patient finding the procedure too uncomfortable.

 

Are there any side effects?

Hormone IUS: In the first 3-6 months following IUS insertion you may have irregular, prolonged or frequent bleeding but menstrual bleeding patterns tend to improve with time. By 1 year, it is usual to have infrequent or no menstrual bleeding. Hormone side effects are uncommon but can occur due to the body absorbing small amounts of the hormone. These includes acne, breast tenderness, headaches and mood changes. These usually settle within 3-6 months.

Copper IUD: Periods can be heavier, longer and more painful. This often improves after the first few months after insertion.

What can I expect during the fitting?

Some discomfort or pain is possible during the insertion. You may wish to take a painkiller (e.g. paracetamol) prior to the appointment. The clinician will need to do an internal examination before the fitting. There will be an assistant present with the clinician.

When can it be fitted?

The IUD is ideally fitted during your menstrual cycle when the cervix is slightly dilated. However, it can be fitted at any time in the menstrual cycle as long as the clinician is reasonably certain there has been no risk of pregnancy. This means using other contraception reliably 100% of the time up until the fitting, or abstaining from sex.

When will it start working?

A hormone IUS will take 7 days to start working (prevent pregnancy), unless fitted within 7 days of the menstrual period starting (in which case it works straight away).

A copper IUD will start working (prevent pregnancy) straight away after fitting.

If you are swapping from another method of contraception, double check with your clinician when you can start relying on the IUD for contraception.

What if I want to conceive?

There is no delay in the return of fertility once the IUD has been removed. Removal is generally a straight forward procedure that can be performed in the surgery.

Is there anything I should look out for afterwards?

It is advised to check your threads once a month, usually after a menstrual period (if you have them).

If at any time, you develop fever or chills with pelvic pain or tenderness, severe cramping or unusual vaginal bleeding, contact your doctor.

If you cannot feel your coil threads (or can feel the plastic stem of the IUD), it may have been expelled or perforated the uterus. Use additional contraception (condoms or avoid sex) and book an appointment to see your doctor. They will examine you and if the threads are not visible will refer you for a scan to assess the location of the coil.

Do I need any follow up?

Make an appointment with the clinician who fitted your IUD about 4-6 weeks after it has been fitted. This is to check the IUD is in place.

Renewal

• Mirena® 5 years
• Jaydess® 3 years
• Copper IUD 5 – 10 years depending on the type used

 

If you would like to discuss a coil, or would benefit from advice and guidance on the contraceptive choices available, please call the surgery to make an appointment with Doctor Alice Scott on 01277 201001.