An IUD prevents pregnancy far better (0.1 to 0.8% typical failure) than the pill (7%), but the pill gives you same-day control over starting and stopping.
The effectiveness gap is structural: the pill's 7% failure rate is almost all missed-dose error, while an IUD has no daily task to get wrong. Duration differs too: an IUD works 3 to 10 years depending on the device; the pill works only as long as you take it daily. The pill's advantages are real: stop anytime without a procedure, usually lighter and more predictable periods, and no insertion appointment. IUD trade-offs: insertion can be painful, removal needs a clinician, hormonal versions often lighten or stop periods, and the hormone-free copper IUD can make periods heavier. Neither method protects against STIs. Decide by priority: maximum effectiveness and zero maintenance point to the IUD; flexibility, cycle control, and avoiding a procedure point to the pill. Both are fully reversible, so choosing one is not locking the other out.
What to do
Common questions
IUD vs the pill: how do I choose?
The core trade: an IUD is far more effective, the pill is far more controllable. On effectiveness, it is not close. IUDs fail 0.1 to 0.4% (hormonal) or 0.8% (copper) in a typical year; the pill fails 7%, almost entirely because of missed or late doses. An IUD is placed once and works for 3 to 10 years depending on the device, with nothing to remember and nothing to refill. The pill demands daily same-time action forever. Where the pill wins is control and reversibility on your own terms: you can start or stop it any day without an appointment, while an IUD needs a clinician for both placement and removal, and placement hurts for many people. Periods differ too: hormonal IUDs usually lighten periods or stop them, the copper IUD is hormone-free but can make periods heavier and crampier, and the pill typically makes periods regular and predictable. Neither protects against STIs. A practical way to decide: if your top priority is not getting pregnant and you dislike daily tasks, get the IUD. If you value same-day start and stop, predictable cycles, or you want to try hormones before committing to a device, start with the pill. You can always switch.