Long-Acting Reversible Contraception

Long-acting reversible contraception (LARC) refers to the contraceptive methods that, once placed, provide several years of pregnancy prevention without requiring ongoing user action: subdermal progestin implants and intrauterine devices (both copper and levonorgestrel-releasing). Because their effectiveness does not depend on daily adherence, LARC methods have the smallest gap between typical-use and perfect-use effectiveness, and they feature prominently in adolescent contraceptive guidance.

Definition

Long-acting reversible contraception comprises intrauterine devices and subdermal implants that deliver continuous, multi-year, fully reversible pregnancy prevention without requiring user action between placement and removal.

Scope

This topic covers what distinguishes LARC methods from user-dependent methods, why their effectiveness is so consistent, and how professional guidance frames their use among adolescents. It is a reference-educational overview; it does not provide insertion technique, eligibility determinations, or individualized recommendations.

Core questions

• What methods constitute long-acting reversible contraception, and how long do they act?
• Why is LARC effectiveness so consistent compared with user-dependent methods?
• Why is LARC emphasized in adolescent reproductive health guidance?
• What considerations shape LARC continuation and access for adolescents?

Key concepts

• Subdermal contraceptive implant
• Copper intrauterine device
• Levonorgestrel intrauterine device
• User-independent effectiveness
• Reversibility and continuation
• Top-tier effectiveness
• Adolescent access and counseling

Mechanisms

LARC methods achieve their effectiveness by removing the need for recurrent user action. The subdermal implant releases a progestin (etonogestrel) that suppresses ovulation and thickens cervical mucus over several years. The levonorgestrel intrauterine device releases progestin locally, thickening cervical mucus and altering the endometrium. The copper intrauterine device creates an intrauterine environment toxic to sperm and ova. Because contraceptive coverage continues uninterrupted between placement and removal, typical-use failure approaches the low perfect-use failure seen for these methods, which is the central reason they are classed in the top tier of contraceptive effectiveness.

Clinical relevance

The user-independence of LARC explains why these methods show such consistent real-world effectiveness and why professional bodies discuss them as first-line options to offer adolescents alongside full counseling on all methods. This entry describes the rationale and category for orientation; decisions about whether a LARC method is appropriate for an individual depend on history, preferences, and clinician assessment and are outside its scope.

Epidemiology

Prospective cohort data such as the Contraceptive CHOICE Project showed substantially lower contraceptive failure with LARC than with pills, patches, or rings, with the difference most pronounced among younger users (Winner et al., 2012). Population surveys have documented rising LARC uptake over time (Kavanaugh & Jerman, 2018).

Evidence & guidelines

Professional guidance, including an ACOG committee opinion addressing adolescents and the CDC selected practice recommendations, frames LARC as appropriate to offer adolescents within a model of comprehensive, non-coercive counseling (ACOG, 2018; Curtis et al., 2016). These are cited to show how the field reasons about LARC, not to direct individual care.

Debates

How should LARC be promoted without becoming coercive?

Because LARC is highly effective and user-independent, guidance stresses that it be offered within shared decision-making that respects autonomy and avoids steering, particularly for adolescents and historically marginalized groups; the balance between promoting effective methods and protecting reproductive autonomy is an ongoing concern.

Seminal works

• winner-2012
• acog-735-2018

Frequently asked questions

What methods count as LARC?

Long-acting reversible contraception comprises subdermal progestin implants and intrauterine devices (copper and levonorgestrel-releasing); all provide multi-year, reversible contraception without ongoing user action.

Why is LARC effectiveness so consistent?

Because effectiveness does not depend on remembering to take or use the method, the real-world (typical-use) failure rate is very close to the low perfect-use rate, unlike methods that require daily or per-act adherence.