Intrauterine Contraception

Intrauterine contraception is a long-acting reversible method in which a small device placed in the uterine cavity prevents pregnancy for 3 to 12 years, depending on the device. Two classes exist: copper-bearing devices and levonorgestrel-releasing devices. Both are highly effective, need no action from the patient after insertion, act immediately or within 7 days, and allow return of fertility as soon as the device is removed.

Classification.

• Copper-bearing devices: framed T-shaped devices (copper T 380A and lower copper surface area designs) and frameless devices.
• Levonorgestrel-releasing devices: 52 mg, 19.5 mg and 13.5 mg reservoir devices.

Mechanism. Copper ions are toxic to sperm and ova and alter uterine and tubal fluid, so fertilisation is prevented. Levonorgestrel thickens cervical mucus, suppresses the endometrium and blocks sperm transport; ovulation continues in most cycles.

Effectiveness. In the first year, the copper T 380A carries about 6 pregnancies per 1,000 women with perfect use and 8 per 1,000 with typical use. The levonorgestrel 52 mg device carries about 2 per 1,000 with both perfect and typical use, because user error is negligible.

Duration.

Return to fertility. Fertility returns to the patient’s baseline immediately after removal, with no delay in conception.

Ideal candidates. Any patient who wants highly effective, long-term contraception that does not depend on daily or monthly action, including nulliparous patients, adolescents, breastfeeding patients and those with contraindications to oestrogen.

History and examination. Take a menstrual, obstetric, sexual and STI risk history. A bimanual and speculum examination is essential before insertion to assess uterine size, position and cervical health and to exclude pelvic infection.

Investigations. No routine blood tests are needed. Exclude pregnancy clinically or by test. Offer STI testing to those at increased risk, without delaying insertion in asymptomatic patients. Haemoglobin is useful before a copper device if anaemia or heavy bleeding is suspected.

Key eligibility categories (both device classes).

• Category 4 (do not insert): pregnancy; unexplained vaginal bleeding before evaluation; current pelvic inflammatory disease or purulent cervicitis; puerperal sepsis or immediate post-septic abortion; known pelvic tuberculosis; cavity-distorting fibroids or uterine anomalies, including a uterine cavity under 6 cm; malignant gestational trophoblastic disease or persistently raised beta hCG.
• Category 3: 48 hours to 4 weeks postpartum; AIDS when initiating, unless clinically well on antiretroviral therapy; very high individual likelihood of gonorrhoea or chlamydia exposure; gestational trophoblastic disease with falling or undetectable beta hCG.
• Category 2: menarche to under 18 years and nulliparity; second-trimester abortion without sepsis; past pelvic inflammatory disease without later pregnancy; increased STI risk.
• Levonorgestrel devices only: current breast cancer is category 4; acute deep vein thrombosis or pulmonary embolism, severe decompensated cirrhosis, hepatocellular adenoma or hepatoma, and systemic lupus erythematosus with positive or unknown antiphospholipid antibodies are category 3.

Interactions. Enzyme-inducing medicines, including rifampicin and antiseizure medicines, do not reduce the effectiveness of either device class.

Counselling points. Explain expected bleeding changes for the chosen device, the small risks of expulsion and perforation, the lack of STI and HIV protection (dual protection with condoms), and the patient’s right to removal at any time without justification.

Pregnancy exclusion. The provider can be reasonably certain the patient is not pregnant if any one applies: within 7 days of the start of a normal menses (12 days for copper devices); within 7 days after abortion or miscarriage; within 4 weeks postpartum (insertion only within 48 hours); fully breastfeeding, amenorrhoeic and under 6 months postpartum; abstinent since the last normal menses; or correctly using a reliable method. Otherwise use a sensitive urine pregnancy test, remembering that a test is unreliable within 3 weeks of unprotected sex.

Start timing.

Follow up. Review 3 to 6 weeks after insertion to check threads, bleeding and symptoms. Teach the patient to return with fever, increasing pelvic pain, dyspareunia, abnormal discharge, a missed period, felt device, or a partner reporting thread or stem contact.

Removal and replacement. Remove at any time on request. Replace at the end of the device duration; immediate reinsertion through the same visit is acceptable.

Perimenopause. A copper device inserted at age 40 or over may remain until 12 months after the last menstrual period.

Expected effects. Copper devices increase menstrual volume, duration and cramping, most in the first 3 to 6 months. Levonorgestrel devices cause irregular light bleeding in the first 3 to 6 months, then reduced bleeding or amenorrhoea.

Expulsion. About 1 in 20 devices are expelled in the first year, more often in the first 3 months, after post-placental insertion, in nulliparous and adolescent patients and in those with heavy menstrual bleeding.

Perforation. About 1 to 2 for every 1,000 insertions, higher during breastfeeding and in the first months after birth. Many are partial and present later as missing threads.

Infection. Pelvic inflammatory disease risk rises only in the first 20 days and relates to existing cervical infection at insertion. Treat with the device in place; remove only if no response after 48 to 72 hours of antibiotics.

Pregnancy with a device in place. Pregnancy is rare, but a higher proportion of those that do occur are ectopic. Exclude ectopic pregnancy by ultrasound. If intrauterine and the threads are visible in the first trimester, offer gentle removal.

Referral and escalation. Refer urgently for suspected perforation, ectopic pregnancy, sepsis or a device not located on ultrasound. Refer to a specialist for difficult removals and embedded devices.