What are the types of long‑acting reversible contraceptives (LARCs), including intrauterine devices (IUDs) and subdermal implants, and their typical durations and contraindications?

Types of Long-Acting Reversible Contraceptives (LARCs)

LARC methods include intrauterine devices (IUDs)—both hormonal levonorgestrel and non-hormonal copper—and subdermal etonogestrel implants, all offering highly effective contraception with failure rates <1% and durations ranging from 3 to 10 years. 1

Available LARC Methods in the United States

Intrauterine Devices (IUDs)

Hormonal IUDs (Levonorgestrel):

• Mirena: 52 mg levonorgestrel, FDA-approved for 5 years 1
• Liletta: 52 mg levonorgestrel, FDA-approved for 5 years 1
• Kyleena: 19.5 mg levonorgestrel, FDA-approved for 5 years 1
• Skyla: 13.5 mg levonorgestrel, FDA-approved for 3 years 1

Non-Hormonal IUD:

• Paragard (Copper T380-A): Copper-containing IUD, FDA-approved for 10 years 1
• Can be used as emergency contraception within 5 days of unprotected intercourse 1, 2

Subdermal Implant

Nexplanon (Etonogestrel):

• Single-rod implant containing etonogestrel (active metabolite of desogestrel) 1
• FDA-approved for 3 years of use 1, 3
• Failure rate <0.05%, making it one of the most effective contraceptive methods available 4, 3
• Inserted subdermally in the upper arm by trained clinicians 1

Efficacy and Duration Summary

All LARC methods have typical use failure rates of <1%, rivaling tubal sterilization 1, 5. The key advantage is that "typical use" and "perfect use" failure rates are nearly identical because these methods are not user-dependent 5, 2.

Contraindications to LARC Methods

IUD Contraindications (US MEC Category 4 - Unacceptable Risk):

All IUDs:

• Distorted uterine cavity 1
• Current cervical cancer 1
• Current endometrial cancer 1
• Malignant gestational trophoblastic disease 1
• Current pelvic inflammatory disease 1
• Post-septic abortion 1
• Puerperal sepsis 1
• Purulent cervicitis 1
• Pelvic tuberculosis 1
• Unexplained vaginal bleeding 1

Copper IUD specifically:

• Wilson disease 1

Levonorgestrel IUD specifically:

• Current breast cancer 1

Subdermal Implant Contraindications:

Nexplanon (US MEC Category 4):

• Current breast cancer (the only absolute contraindication) 1, 4, 6

Clinical Advantages for Specific Populations

LARC methods are particularly appropriate for:

• Women with conditions where estrogen is contraindicated (thromboembolic disease, stroke, cardiovascular disease, migraine with aura) 1, 6
• Women with SLE or antiphospholipid antibodies (progestin-only methods or copper IUD preferred over estrogen-containing contraceptives) 1
• Medically complex women including those with diabetes, chronic renal/liver disease, solid organ transplant, peripartum cardiomyopathy, cystic fibrosis 1, 4
• Nulliparous adolescents (safe and appropriate despite historical misconceptions) 1, 7
• Immediate postpartum period (can be placed during delivery hospitalization) 1

Important Clinical Pearls

• IUDs do not cause infertility in nulliparous women, and fertility returns rapidly after removal 1
• Pelvic infection risk with IUDs occurs only during the first 21 days after insertion; beyond this period, IUDs do not increase STI or PID rates 1
• STI screening can be performed on the day of IUD insertion, with treatment provided without IUD removal if needed 1
• Immediate postpartum IUD insertion (within 10 minutes of placental delivery) has higher expulsion rates (~10-24%) but superior continuation rates compared to interval placement due to reduced access barriers 1
• Backup contraception is needed for 7 days after implant insertion 1
• Common reason for implant discontinuation is unpredictable bleeding or spotting 1