Contraception - IUC
Exam Tips
- For OSCE counselling, contrast key timing: Cu-IUD works immediately; LNG-IUD needs 7 days for full contraceptive effect.
- Quote effectiveness accurately: very low failure with both perfect and typical use, and efficacy is not reduced by BMI or enzyme-inducing drugs.
- Remember UK extension rules: 52 mg LNG-IUD inserted at >=45 years can be used to age 55; Cu-IUD >=300 mm2 inserted at >=40 years can continue until menopause.
- If threads are not visible, think in order: expulsion, perforation, pregnancy, or retracted threads; assess pregnancy first, then localise device (usually ultrasound).
- State clearly in viva: IUC does not protect against STIs, so condom advice remains essential.
- Image-based exams often test correct position: fundal T-arms fully deployed with stem central in cavity (see standard pelvic ultrasound diagrams of IUD position).
Definition
Intrauterine contraception (IUC) is a long-acting reversible contraceptive method delivered via a device placed in the uterine cavity, providing highly effective contraception for 3-10 years depending on type. In UK practice, this includes levonorgestrel intrauterine devices (LNG-IUDs) and copper intrauterine devices (Cu-IUDs), with lower typical-use failure than short-acting user-dependent methods.
Pathophysiology
Both LNG-IUDs and Cu-IUDs act mainly before fertilization. LNG-IUDs (e. g, 52 mg, 19.5 mg, 13.5 mg systems) thicken cervical mucus, induce marked endometrial suppression/atrophy, and may inhibit ovulation in a minority of users; most users continue ovulating, so systemic ovarian suppression is limited. Cu-IUDs release copper ions that impair sperm function and viability and reduce fertilization; they also trigger a local sterile endometrial inflammatory response that can reduce implantation potential. Contraceptive efficacy is strongly linked to correct fundal placement of the T-shaped device.
Risk Factors
- Higher expulsion risk in first year, especially first 3 months after insertion
- Immediate postpartum insertion (higher expulsion than interval insertion)
- Adolescence
- Insertion after late first- or second-trimester surgical abortion
- Fibroids/menorrhagia or uterine cavity distortion
- Previous IUC expulsion
- Concurrent menstrual cup use (possible increased expulsion risk)
- STI exposure at insertion increases early post-insertion pelvic infection risk
Clinical Features
Symptoms
- Usually asymptomatic once established
- Insertion-related cramping pain (typically mild-moderate)
- Unscheduled bleeding/spotting in early months
- LNG-IUD: lighter periods, possible amenorrhoea over time
- Cu-IUD: may have heavier or more painful menses
- Possible hormonal-type symptoms with LNG-IUD (acne, headache, breast tenderness, mood change)
- Thread concerns (cannot feel threads, concern about displacement/expulsion)
Signs
- Visible threads at external cervical os on speculum examination (if correctly positioned and strings accessible)
- Absent/non-visible threads (may represent retracted strings, expulsion, perforation, or pregnancy)
- Partial expulsion: stem visible in cervix
- Pelvic/uterine tenderness or cervical motion tenderness if pelvic infection
- Malposition features on ultrasound (non-fundal, rotated, embedded, cervical position)
Investigations
Management
Lifestyle Modifications
- Shared decision-making on device type, bleeding profile, duration, and non-contraceptive benefits
- Advise condoms for STI protection because IUC does not protect against STIs
- Safety-net urgently for severe pain, heavy bleeding, fever, offensive discharge, or positive pregnancy test
- Teach thread checking after menses if patient wishes, and advise review if threads are absent/shorter/longer
- Arrange follow-up if symptoms suggest expulsion, malposition, infection, or intolerance
Pharmacological Treatment
Levonorgestrel-releasing intrauterine contraception (progestogen IUD)
- Mirena 52 mg LNG intrauterine device (licensed contraception up to 8 years)
- Levosert 52 mg LNG intrauterine device
- Benilexa 52 mg LNG intrauterine device
- Kyleena 19.5 mg LNG intrauterine device (licensed contraception up to 5 years)
- Jaydess 13.5 mg LNG intrauterine device (licensed contraception up to 3 years)
Inserted by trained clinician. Contraceptive effect is established after 7 days, so additional contraception is needed for the first 7 days unless timing criteria are met. 52 mg LNG-IUD inserted at age >=45 years can generally be continued for contraception until age 55. Discuss possible small increase in breast cancer risk with current/recent hormonal contraception, and counsel regarding irregular bleeding and hormonal adverse effects.
Copper intrauterine contraception (non-hormonal IUD)
- Copper T380A (380 mm2 copper)
- Multiload Cu375 (375 mm2 copper)
- GyneFix 330 (330 mm2 copper)
- Novaplus T380 Ag (380 mm2 copper)
Effective immediately after insertion, including as emergency contraception, with no hormone-related adverse effects and no enzyme-inducer interaction. Devices with >=300 mm2 inserted at age >=40 years can usually remain until menopause. Warn about possible heavier/longer or more painful periods.
Analgesia for insertion discomfort
- Ibuprofen 400 mg orally 1 hour pre-procedure (if suitable)
- Paracetamol 1 g orally pre- or post-procedure
Supportive pain management may improve tolerability; avoid NSAIDs in contraindicated patients (e. g, active peptic ulcer disease, NSAID hypersensitivity, significant renal impairment).
Surgical / Interventional
- Office transcervical insertion of LNG-IUD or Cu-IUD by trained practitioner
- Device removal by thread traction in clinic
- Hysteroscopic removal if threads not visible or device embedded
- Urgent specialist management for suspected uterine perforation
Complications
- Expulsion (overall about 1 in 20, highest early after insertion)
- Unscheduled bleeding or altered menstrual pattern
- Insertion-related pain/vasovagal episode
- Pelvic infection risk increase in first 3 weeks post-insertion (overall low)
- Uterine perforation (rare but serious)
- Malposition (low-lying, rotated, embedded, cervical, incorrectly deployed)
- Non-visible threads
- Contraceptive failure including ectopic pregnancy risk if pregnancy occurs
- Very rare pelvic actinomycosis with long-term use
Prognosis
IUC offers excellent long-term contraceptive efficacy with rapid return of fertility after removal. Most adverse effects are early and improve with time; serious complications are uncommon when insertion technique, infection risk assessment, and follow-up safety-netting are appropriate.
Sources & References
🏥BMJ Best Practice(1)
💊BNF Drug References(11)
- Desogestrel[management.pharmacological]
- Drospirenone[management.pharmacological]
- Drospirenone with estetrol[management.pharmacological]
- Estradiol with nomegestrol[management.pharmacological]
- Ethinylestradiol with etonogestrel[management.pharmacological]
- Ethinylestradiol with norelgestromin[management.pharmacological]
- Etonogestrel[management.pharmacological]
- Intra-uterine contraceptive devices (copper)[management.pharmacological]
- Levonorgestrel[management.pharmacological]
- Medroxyprogesterone acetate[management.pharmacological]
- Norethisterone[management.pharmacological]
✅NICE Guidelines(1)
- Contraception - IUC[overview]
📖Textbook References(1)
- Emergencies in - Obstetrics and Gynaecology, Second Edition (Stergios K. Doumouchtsis, S. Arulkumaran) (Z-Library).pdf(pp. 297, 298)[context]