A Working Checklist for Contraception

The range of methods used to prevent pregnancy, hormonal and non-hormonal. Effectiveness in practice differs substantially from effectiveness in perfect use, and the gap is largest for the methods people rely on most.

Key takeaways

• Most effective methods: implant, intrauterine device and intrauterine system
• Long-acting methods: do not depend on remembering anything
• Most useful single change: Ask specifically about long-acting methods, which are the most effective.
• Commonest mistake: Assuming a method works the same in real use as in perfect use.
• See a doctor if any of the signs under "When to speak to a doctor" below apply to you.

Do

• Ask specifically about long-acting methods, which are the most effective
• Get emergency contraception as early as possible; pharmacies supply it
• Review your method when your circumstances or medications change
• Continue contraception until advised it is no longer needed

Do not

• Assuming a method works the same in real use as in perfect use
• Stopping contraception on the basis of irregular periods alone
• Combined hormonal methods without discussing migraine with aura, smoking over 35, or clot history

The numbers behind the list

Those two lists follow from the published figures here.

If you change one thing

Ask specifically about long-acting methods, which are the most effective. If you only change one thing, make it that.

Where to go next

• Contraception: Just the Figures
• Contraception: Sorting the Evidence From the Noise
• Contraception — the reference entry
• Preconception Health: What the Evidence Actually Says
• Bone Health in Women: What the Evidence Actually Says

When to speak to a doctor

Seek urgent medical help for calf pain or swelling, chest pain, severe breathlessness, sudden severe headache, weakness on one side or vision loss while using combined hormonal contraception — these can indicate a clot or stroke. Tell your prescriber about migraine with aura, smoking over 35, high blood pressure or a history of clots.

Where this comes from

• NICE — Contraception clinical knowledge summary
• NHS — Contraception guide

How this page was put together

Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarised or generalised beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.

Medical disclaimer

This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to a GP, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 999.