I don’t have access to live tool results in this turn, but I can provide up- to-date, evidence-based context about how effective an IUD is based on reputable sources and current medical guidelines. Direct answer

• Overall effectiveness: Intrauterine devices (IUDs), including both hormonal and copper types, are among the most effective forms of reversible contraception, with a typical-use effectiveness of over 99% and a failure rate well below 1% per year. Once inserted, they work without user action for several years (typically 3–10 years depending on the brand and type).

• Comparison by type:
  • Hormonal IUDs (e.g., levonorgestrel-releasing) and copper IUDs (non-hormonal) both have failure rates under 1% per year. In practical terms, fewer than 1 in 100 users will become pregnant in the first year of typical use, and the injury-free, long-acting nature makes them very reliable. The exact failure rate is very low for both types, with minor differences in side effects and management rather than in overall effectiveness.

• Timeframe of protection:
  • Hormonal IUDs: Typically protect for 3 to 7 years depending on the product (e.g., 3–5 years for some, up to 7 for others). Copper IUDs: Usually last 10 to 12 years, depending on the brand and regulatory approvals. Removal or replacement returns you to non-IUD fertility promptly after removal.

• Emergency contraception use:
  • Copper IUD: When inserted within about five days after unprotected intercourse, it is over 99% effective at preventing pregnancy and is the most effective form of emergency contraception. Hormonal IUDs are not used for emergency contraception.

• Real-world considerations:
  • IUDs offer high effectiveness with minimal daily upkeep, which makes them a strong option for people seeking long-acting contraception without frequent attention. Side effects, such as changes in bleeding patterns or hormonal effects (for hormonal IUDs), vary by individual and product, but do not typically compromise the overall effectiveness.

Key takeaways

• If the goal is maximum, long-term effectiveness with minimal daily maintenance, an IUD is among the best choices, with proven >99% effectiveness for both hormonal and copper versions.

• For emergency contraception, the copper IUD is the most effective option when used within the recommended window after unprotected sex.

If you’d like, I can tailor this to your situation (age, desire for hormonal vs non-hormonal, planned duration of contraception, pregnancy considerations, or prior medical history) and outline the pros/cons of each IUD type for you.