01Purpose and principlesWhat the treatment does and how it fits into care.
Copper IUDs release copper ions that impair sperm function and fertilisation; LNG-IUDs release local levonorgestrel, thickening cervical mucus, suppressing endometrial proliferation and sometimes inhibiting ovulation. Both deliver highly effective long-acting reversible contraception without daily action and fertility returns promptly after removal. The copper device is hormone-free and works immediately but can worsen bleeding and dysmenorrhoea. LNG systems commonly cause irregular bleeding initially, then reduce menstrual loss and may cause amenorrhoea.
Choose the device and duration by its exact licence and indication. Copper IUDs are licensed for five or ten years depending on model, with extended use for some devices inserted at age 40 or older under specialist guidance. The 52 mg LNG-IUD landscape has changed: Mirena, Levosert and Benilexa have current eight-year contraceptive licences, while their licensed duration for heavy menstrual bleeding and use as the progestogen component of HRT is not automatically eight years. Record brand, dose, insertion date, indication and replacement date rather than writing only coil.
The copper IUD is first choice for emergency contraception because it is the most effective method and becomes ongoing contraception. It may be inserted within five days of the first episode of unprotected intercourse in the cycle, or within five days of the earliest likely date of ovulation when that can be estimated. Oral emergency contraception does not make an otherwise unsafe insertion safe. A 52 mg LNG-IUD has evidence as emergency contraception but is not the UK standard emergency method in current CoSRH guidance; offer the copper device.
Pre-insertion assessment includes pregnancy exclusion from history and testing, last intercourse, current method and emergency need. Ask about pelvic infection symptoms, STI exposure, unexplained bleeding, cervical or endometrial risk, uterine anomalies, fibroids and prior difficult procedures. Pelvic examination establishes uterine size, position and tenderness; speculum examination assesses cervix. Routine ultrasound is unnecessary, but use it when anatomy, cavity distortion, position or prior perforation raises a specific question.
Use trauma-informed procedural consent. Explain each step, offer a chaperone, agree a stop signal and discuss pain relief rather than promising mild discomfort. Options depend on setting and may include pre-procedure oral analgesia, local anaesthetic techniques and referral for additional support or sedation. Cervical screening is not a prerequisite. Test for chlamydia and gonorrhoea at insertion when indicated rather than delaying routine care in an asymptomatic patient; do not insert with current purulent cervicitis or known untreated pelvic infection.
Complications are uncommon but need clear safety-netting. Uterine perforation occurs most often during insertion and risk is higher postpartum and during breastfeeding. Expulsion is most frequent in the first year and after immediate postpartum placement; heavy bleeding and cavity distortion can increase risk. Pelvic infection risk is concentrated in the first 20 days and reflects infection present at insertion rather than a persistent device effect. Vasovagal symptoms during instrumentation require stopping, positioning and observation.
If threads cannot be seen, exclude pregnancy and advise additional precautions until location is known. Ultrasound is the first localisation test; if the device is not within the uterus, abdominal or pelvic radiography can identify a perforated radiopaque device. Do not explore blindly. If pregnancy occurs, establish location urgently. For an intrauterine pregnancy, discuss miscarriage, infection and preterm risks and seek specialist removal advice when threads are accessible, balancing procedural loss against leaving the device in place.
Removal requires consent and planning around recent intercourse. Sperm may survive up to seven days, so unprotected sex before removal can create pregnancy risk if a replacement is not immediately effective. Replace seamlessly where possible or use abstinence or condoms for seven days before planned removal. Removal at any time should be available when requested; neither clinician preference nor a non-medical partner can veto it.
Key points
- Copper IUD and levonorgestrel IUD are over 99% effective, rapidly reversible and unaffected by hepatic enzyme-inducing medicines; neither protects against sexually transmitted infections.
- The copper IUD is the most effective emergency contraception: insert within five days after the first unprotected intercourse in the cycle or within five days of the earliest estimated ovulation, whichever rule permits later insertion.
- Copper devices act immediately and commonly make periods heavier, longer or more painful; LNG-IUDs usually cause early irregular bleeding followed by lighter bleeding or amenorrhoea.
- Duration is product-specific. Current 52 mg levonorgestrel systems used for contraception may have an eight-year licence, while duration for heavy menstrual bleeding or HRT endometrial protection is shorter and indication-specific.
- Before insertion, reasonably exclude pregnancy, assess infection risk and unexplained bleeding, consider uterine cavity distortion and obtain specific consent for pain, perforation, expulsion, infection and failure.
- Offer analgesia and discuss the full range of pain-control options before insertion; use an assistant or chaperone and stop whenever the patient asks.
- Routine prophylactic antibiotics are not indicated. If asymptomatic STI risk is identified, testing can usually occur at insertion, with prompt treatment and follow-up of a positive result.
- Missing threads do not prove expulsion. Advise condoms or abstinence, assess emergency contraception and pregnancy, then locate the device by ultrasound before instrumenting the uterine cavity.
02Indications, selection and cautionsWho may benefit, who needs urgent treatment and important alternatives.
Periods may become heavier, longer and more painful, making baseline heavy menstrual bleeding or dysmenorrhoea central to method choice.
Spotting and irregular bleeding are common for the first months before bleeding usually becomes lighter and may stop altogether.
Newly long or absent threads, feeling the device, fresh heavy bleeding or loss of a previously established bleeding effect can indicate displacement.
Unexpected severe insertion pain, persistent pelvic or abdominal pain, absent threads or a device not seen within the uterus requires localisation.
Pelvic pain, cervical excitation, purulent discharge, fever or systemic illness in the weeks after insertion supports prompt PID assessment.
03Assessment before treatmentTests and checks that guide safe selection.
Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.
- 01
Pregnancy assessmentFirst step - Why
- Reasonably exclude established or very early pregnancy before insertion and assess risk after device failure.
- Interpretation and limitations
- Combine test with menstrual, intercourse and contraception dates. Insertion should wait when pregnancy cannot be reasonably excluded, except that a copper IUD may itself meet emergency criteria.
- 02
Bimanual and speculum examination - Why
- Assess uterine position, size, tenderness and cervical appearance immediately before insertion.
- Interpretation and limitations
- Findings guide sound length and technique. Purulent cervicitis, significant tenderness, unexplained bleeding or a distorted cavity changes the plan.
- 03
Targeted chlamydia and gonorrhoea NAAT - Why
- Identify infection when age, exposure or local screening criteria indicate risk.
- Interpretation and limitations
- Same-day testing is usually compatible with insertion in an asymptomatic patient. Treat a positive result promptly; symptomatic infection warrants assessment before placement.
- 04
Transvaginal ultrasound - Why
- Locate a device when threads are absent, symptoms suggest malposition or anatomy is uncertain.
- Interpretation and limitations
- Confirm fundal intrauterine position and relation to myometrium. A device not visualised in the cavity requires pregnancy assessment and radiographic localisation.
- 05
Abdominal or pelvic radiograph - Why
- Locate a radiopaque IUD not seen within the uterus on ultrasound.
- Interpretation and limitations
- An extrauterine device supports perforation and specialist removal planning; a negative film with prior confirmed placement supports unrecognised expulsion.
04Treatment approachPreparation, options, escalation and aftercare.
01First-line emergency optionOffer the copper IUD firstFirst stepFirst lineUnprotected intercourse falls within a recognised intrauterine emergency-contraception window.+
- 1Establish every intercourse date, cycle timing, current contraception, pregnancy possibility, infection symptoms and patient preference without delaying access.
- 2Offer a copper IUD as the most effective emergency method, using the five-day intercourse or earliest-ovulation rule and explaining immediate ongoing protection.
- 3If it is declined or unsuitable, provide the best oral emergency option promptly and arrange an ongoing method, backup and pregnancy test at 21 days.
02Routine insertionPrepare, consent and place safelyA patient chooses an intrauterine method and pregnancy can be reasonably excluded.+
- 1Confirm brand, indication, bleeding preference, uterine and infection history, STI testing need, analgesia plan, chaperone and voluntary procedural consent.
- 2Perform bimanual and speculum assessment, use aseptic trained technique, sound and insert according to product instructions, stopping if pain or anatomy makes continuation unsafe.
- 3Record device, batch, cavity length, thread length, insertion and replacement dates and give written advice for pain, bleeding, infection, expulsion, pregnancy and removal.
03Missing threadsProtect first, then locateThreads cannot be seen or felt, or their length has changed materially.+
- 1Advise condoms or abstinence, assess recent intercourse for emergency contraception and perform a pregnancy test, including later repeat testing where necessary.
- 2Exclude simple cervical retraction with appropriate trained assessment, then arrange ultrasound without blind intrauterine instrumentation.
- 3AlternativeUse radiography if not seen in the uterus and refer malposition, embedment or perforation for specialist management while maintaining alternative contraception.
04Pregnancy in situLocate urgently and reduce harmA pregnancy test is positive while an IUD is believed to be present.+
- 1Assess haemodynamic state, pain and bleeding and arrange urgent pregnancy-location evaluation because ectopic pregnancy must be excluded.
- 2For intrauterine pregnancy, discuss the patient’s pregnancy intention and increased miscarriage, infection and preterm risks if the device remains.
- 3Seek specialist removal when threads are visible or retrieval is considered, and provide emergency care for worsening pain, bleeding, fever or collapse.
05Regimens, contraindications and interactionsTreatment details and the circumstances that modify them.
Copper intrauterine device
Insert one appropriately licensed copper-bearing device using trained aseptic technique; for emergency contraception insert within five days of first unprotected intercourse in the cycle or within five days of earliest estimated ovulation.Avoid when pregnancy cannot be excluded outside EC criteria, with current pelvic infection or incompatible cavity anatomy; discuss heavier bleeding, pain, perforation, expulsion and copper-specific contraindications.
Levonorgestrel 52 mg intrauterine device
Insert one 52 mg device after pregnancy exclusion and suitability assessment; use the exact brand’s current duration, with Mirena, Levosert and Benilexa licensed for up to eight years for contraception.Contraceptive, heavy-bleeding and HRT replacement intervals differ; assess breast cancer, liver disease, unexplained bleeding, infection and cavity distortion and discuss irregular bleeding, perforation and expulsion.
06Complications, monitoring and follow-upAdverse effects, response and longer-term review.
- Document device name, levonorgestrel dose or copper load, indication, insertion date, current licensed replacement date and any age-related extended-use advice.
- Review severe or persistent pain, fever, offensive discharge, heavy bleeding, dyspareunia, thread change or pregnancy symptoms promptly rather than waiting for routine follow-up.
- Track STI results obtained at insertion to treatment and partner notification while recognising that routine prophylactic antibiotics are not required.
- Reassess abnormal bleeding after the expected settling period, especially postcoital, intermenstrual or postmenopausal bleeding and new pain or anaemia.
- Plan contraception around removal or replacement, accounting for intercourse in the preceding seven days and ensuring removal remains accessible on request.
07Special situationsVariants, exceptions and circumstances that change the usual approach.
Indication controls duration
An eight-year contraceptive licence for a 52 mg LNG-IUD does not automatically extend its heavy-bleeding or HRT endometrial-protection interval.
Copper is the emergency standard
It is more effective than oral emergency contraception and provides immediate ongoing protection when inserted within the recognised timing rules.
Infection risk is front-loaded
The small excess PID risk is concentrated after insertion and relates largely to infection introduced or already present, not years of device use.
Threads are a sign, not a diagnosis
Absent threads may mean cervical retraction, expulsion, malposition or perforation; pregnancy protection and imaging resolve the uncertainty.
Removal has a seven-day history
Recent intercourse matters because viable sperm can predate removal and fertilisation can occur once the contraceptive effect ends.
08Common pitfallsFrequent interpretation and management errors.
- 01
Calling every device a coil without documenting its brand, dose, indication and replacement date.
- 02
Applying an eight-year contraceptive licence to heavy-menstrual-bleeding treatment or HRT protection without checking that indication.
- 03
Using a negative pregnancy test alone to insert after recent unprotected intercourse outside copper-IUD emergency criteria.
- 04
Giving routine prophylactic antibiotics while failing to assess actual STI symptoms and exposure.
- 05
Exploring the uterus blindly when threads are absent instead of protecting against pregnancy and arranging ultrasound.
- 06
Removing an IUD after recent unprotected sex without considering sperm survival, emergency contraception and replacement cover.