The IUD (coil): copper or hormonal, fitting and who should avoid it
In brief
The coil, or intrauterine device (IUD), is long-acting contraception placed in the womb in a few minutes at the practice. There are two types: the copper IUD, which is hormone-free, and the levonorgestrel hormonal IUD, which often makes periods lighter. With a failure rate of less than 1% in the first year, it is one of the most effective methods and can be offered to women who have never had children.
How does an IUD work?
The IUD is a small T-shaped device, about 3 cm long, placed inside the womb. Two fine threads come out through the cervix into the top of the vagina; they are used for checking and removal.
- The copper IUD releases copper ions that are toxic to sperm and prevent fertilisation. It contains no hormones: your cycles stay natural.
- The hormonal IUD releases low doses of a progestogen, levonorgestrel. It thickens cervical mucus, which blocks sperm, and thins the lining of the womb. Ovulation usually continues.
The IUD does not cause an abortion and does not protect against sexually transmitted infections. It is one of the methods described on our contraception methods page; for more extensive procedures, see gynaecological surgery.
Copper or hormonal IUD: which should I choose?
| Criterion | Copper IUD | Hormonal IUD (levonorgestrel) |
|---|---|---|
| Hormones | None | Low dose of progestogen, acting mainly locally |
| How long it lasts | Several years depending on the model (stated in the leaflet and on the card given at fitting) | 3 to 8 years depending on the model (8 years for the 52 mg model) |
| Effect on periods | Periods sometimes heavier and more painful | Periods often lighter, sometimes absent; irregular bleeding in the first months |
| Suited to | Wanting to avoid hormones; emergency contraception | Heavy or painful periods |
| Effectiveness | Less than 1% failure in the first year, with nothing to forget | |
The 52 mg levonorgestrel IUD is also a treatment for heavy periods. A large French study published in 2024 found no increased risk of meningioma with levonorgestrel IUDs, unlike some other progestogens.
Who can have an IUD?
The French College of Gynaecologists and Obstetricians (CNGOF) points out that the IUD suits a very wide range of women: teenagers, women who have never had children, women who have had an ectopic pregnancy, and women living with HIV. It is also suitable for women who cannot take oestrogen (smokers, migraine with aura, previous deep vein thrombosis).
It can be fitted after childbirth, usually from 4 to 6 weeks, or immediately after a surgical (suction) abortion. It is also the most effective emergency contraception up to 5 days after unprotected sex (see emergency contraception).
Who should not have an IUD?
An IUD should not be fitted if you have:
- a current or suspected pregnancy;
- a current genital infection (cervicitis, salpingitis, untreated STI) or an infection after childbirth or an abortion;
- unexplained genital bleeding;
- cancer of the cervix or womb lining;
- a malformation or fibroid that distorts the cavity of the womb.
Reasons specific to each type:
- Copper IUD: copper allergy, Wilson's disease.
- Hormonal IUD: current or recent breast cancer, severe liver disease.
Contrary to old beliefs, a previous ectopic pregnancy or never having had children are not reasons to avoid an IUD. Special situations (anticoagulant treatment, heart valve disease) are assessed case by case.
What happens when an IUD is fitted?
The IUD is fitted at the practice in a few minutes, without general anaesthetic.
- Preliminary consultation: questions about your history, and a gynaecological examination with an internal examination and a speculum check of the cervix, which the CNGOF considers essential. Testing for chlamydia and gonorrhoea is offered depending on your situation; it can be done on the day of fitting if you have no symptoms.
- Timing: at any point in the cycle, as long as pregnancy has been ruled out. Fitting during or just after a period is often easier.
- The procedure: a speculum is inserted, the depth of the womb is measured, then the IUD is inserted through a thin tube. You will feel a cramp, sometimes strong but brief.
- Afterwards: the threads are trimmed to 2 or 3 cm. Cramps and light bleeding are common for the first few days.
The CNGOF does not recommend routine antibiotics or a routine check-up ultrasound. A follow-up appointment may be offered a few weeks after fitting. Arrangements at the practice: average waiting time of one week to 10 days (except during holiday periods); practical advice before fitting is given at the consultation.
What are the side effects and risks of an IUD?
- Changes to periods: heavier with copper, irregular and then often lighter with the hormonal IUD.
- Expulsion: the IUD can come out, especially in the first months, sometimes without you noticing.
- Infection: the risk is mainly linked to the period just after fitting or to an STI. An infection does not necessarily mean the IUD has to come out straight away: the CNGOF recommends treating it and considering removal if there is no improvement after 48 to 72 hours.
- Perforation of the womb: rare, happening at the time of fitting; the IUD is then located by imaging and removed, usually by laparoscopy.
- Pregnancy with an IUD: very rare, but an ectopic pregnancy must then be ruled out. If the pregnancy is in the womb and wanted, the IUD is removed if the threads can be reached.
The smear test for cervical cancer screening is done as normal, on the same schedule as for all women.
What is everyday life like with an IUD?
Once fitted, the IUD needs nothing from you. A few practical points:
- Checking the threads: if you wish, you can feel the threads with your fingertip at the top of the vagina, for example after your period. This is optional, but it helps you notice an expulsion.
- Tampons and menstrual cups: you can use them. With a cup, release the suction fully before removing it and avoid pulling on the threads.
- Sport, sex, travel: no restrictions. The IUD does not move during exercise or sex.
- Medical tests: mention your IUD before an MRI, ultrasound or operation; it does not prevent these tests.
When does an IUD need to be changed or removed?
The IUD must be removed or replaced when it reaches the end of its effective life, shown on the card you are given at fitting. It can be changed in a single appointment: the new one is inserted straight after the old one is removed. If you want to become pregnant, removal is all that is needed; fertility returns immediately.
As the menopause approaches, what to do depends on your age and the type of IUD: your gynaecologist will tell you when it can be removed for good.
When should I see a doctor quickly with an IUD?
See a doctor without delay if you have:
- fever, lower abdominal pain or foul-smelling discharge, especially in the weeks after fitting;
- pain during sex that started after fitting;
- very heavy or persistent bleeding, or bleeding with pain;
- a late period or a positive pregnancy test;
- threads you cannot feel, that feel longer than usual, or an IUD you can feel at the cervix: use condoms until it has been checked.
If you have severe abdominal pain, feel faint or have a high fever, call 15 or 112 in France, or your local emergency number.
Frequently asked questions
Does having an IUD fitted hurt?
Fitting causes a brief cramp, which varies in strength from woman to woman. French guidelines do not recommend routine premedication; talk about any worries before the fitting so that your care can be adapted.
Does an IUD stop you having children later?
No. Fertility returns as soon as it is removed, whatever the type of IUD and however long it was used.
Can an IUD be removed before its expiry date?
Yes, at any time, during an appointment. Removal is quick and usually only mildly uncomfortable.
Can a partner feel the IUD threads?
It is possible but uncommon. If it is a problem, the threads can be shortened during an appointment.
How long can I keep an IUD?
It depends on the model: several years for the copper IUD, and 3 to 8 years for the hormonal IUD (8 years for the 52 mg model, according to its summary of product characteristics). The date for removal or replacement is written on the card you are given when it is fitted.
References
- Vidal F, et al. [Intrauterine contraception: CNGOF Contraception Guidelines]. Gynecol Obstet Fertil Senol, 2018. doi:10.1016/j.gofs.2018.10.004 — PMID 30429071
- ANSM. MIRENA 52 mg (20 microgrammes/24 heures), dispositif intra-utérin : résumé des caractéristiques du produit [Mirena 52 mg intrauterine device: summary of product characteristics] (17/06/2026). Base de données publique des médicaments. base-donnees-publique.medicaments.gouv.fr
- Roland N, et al. Use of progestogens and the risk of intracranial meningioma: national case-control study. BMJ, 2024. doi:10.1136/bmj-2023-078078 — PMID 38537944
Dr Olivier KadochObstetrician-gynaecologist and gynaecological surgeon in Paris (16th and 5th arrondissements). Former chef de clinique-assistant (senior registrar) at the Paris public hospitals (AP-HP); individually accredited by the French National Authority for Health (HAS). RPPS 10003957809. Background and practice locations
A question about your situation?Appointments at the practice or by video consultation, usually within one week to 10 days.
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