See how well 14 methods actually work in real life, not just on paper. Compare perfect use and typical use rates side by side, find out if your weight makes a difference, and pick what fits your body and your life.
Levonorgestrel pill taken as a single dose after unprotected sex. Must be taken within 72 hours, and the sooner the better. Not for regular use.
Ulipristal acetate pill taken as a single dose. Effective up to 120 hours (5 days) after unprotected sex. More effective than Levonelle, especially at higher weights. Not for regular use.
Small rod inserted under the skin of the upper arm. Releases hormones for up to 3 years. Virtually no user error possible.
T-shaped device inserted into the uterus. Releases hormones. Lasts 3 to 8 years depending on brand. No user error once placed.
Non-hormonal IUD. Copper prevents pregnancy. Lasts up to 10 years. Can be used as emergency contraception.
Hormonal injection every 3 months. Typical use is lower because people miss appointments or are late for their next shot.
Daily pill containing oestrogen and progestogen. The large gap shows the impact of forgetting pills, taking them late, or medication interactions.
Daily pill containing only progestogen (the mini pill). Must be taken at the same time daily. The gap is due to forgetting or taking it late.
Skin patch changed weekly. Typical use is affected by forgetting to change it, the patch falling off, or incorrect placement.
Flexible ring inserted into the vagina and changed every 3 to 4 weeks. Typical use is affected by forgetting to change it or the ring falling out.
Used during sex. The large gap is due to incorrect use, breakage, slippage, or not using them every time. The only method that also helps prevent STIs.
Inserted into the vagina before sex. The gap is due to incorrect insertion or not using them every time. Also helps prevent STIs.
Tracking ovulation through temperature, cervical mucus and calendar. The large gap is due to tracking errors, irregular cycles, and lack of partner cooperation.
Silicone cup inserted before sex with spermicide. The gap is due to incorrect placement, not using spermicide, or removing it too soon.
Effectiveness data: all perfect use and typical use rates are sourced from NHS: How well contraception works at preventing pregnancy. Last reviewed by the NHS on 31 January 2024.
For information only. Always talk through your contraceptive options with a GP, sexual health clinic or pharmacist.
| Method | Under 70 kg | 70 to 90 kg | Over 90 kg |
|---|---|---|---|
| Levonelle (levonorgestrel) | About 85% | About 58%, reduced | About 0 to 6%, no better than chance |
| ellaOne (ulipristal acetate) | About 85% | About 85% | About 65%, reduced |
| Copper coil as emergency contraception | Over 99% | Over 99% | Over 99% |
| Contraceptive patch | 91 to 99% | 91 to 99% | Unclear, talk to a clinician |
If you're over 70 kg, the FSRH recommends the copper coil or ellaOne over Levonelle for emergency contraception. A pharmacist may also suggest a double dose of Levonelle, so it's worth asking.
The most common Cliterally community questions, answered.
The implant, hormonal coil (IUS) and copper coil (IUD) are the most effective, at over 99% with typical use. Once they're in, there's nothing to remember, so human error barely comes into it.
With perfect use, the combined pill and the progestogen-only pill are both over 99% effective. In real life that drops to around 91%, which means about 9 in 100 people get pregnant each year. The gap comes from missed or late pills, sickness or diarrhoea, and some medications that stop the pill working properly.
External condoms are 98% effective with perfect use and around 82% with typical use. Internal condoms are 95% and 79%. The gap comes from splitting, slipping, putting one on partway through sex, or not using one every time. Condoms are also the only method that protects against STIs, so they're worth using alongside another method.
It depends which pill. Levonelle drops to around 58% effective between 70 and 90 kg, and it may not work at all over 90 kg. ellaOne holds up better, at around 85% up to 90 kg and around 65% above that. The copper coil is over 99% effective at any weight. If you're over 70 kg, the FSRH recommends the copper coil or ellaOne. A pharmacist may also offer a double dose of Levonelle.
Of the methods on this page, natural family planning has the lowest typical use rate, at around 76%. That means about 24 in 100 people get pregnant each year, mostly because of tracking mistakes and irregular cycles. Diaphragms and caps are 92 to 96% effective with perfect use, but there's no reliable data on how they do in real life.
It's possible but very unlikely. With perfect use, the pill is over 99% effective, so fewer than 1 in 100 people get pregnant in a year. No method is 100%. Things like vomiting, severe diarrhoea or some medications can stop the pill working even when you've taken it on time, so check with a pharmacist if any of those apply.
It's possible but very unlikely. With perfect use, the pill is over 99% effective, so fewer than 1 in 100 people get pregnant in a year. No method is 100%. Things like vomiting, severe diarrhoea or some medications can stop the pill working even when you've taken it on time, so check with a pharmacist if any of those apply.
All the perfect and typical use rates come from the NHS page on how well contraception works, last reviewed in January 2024. The weight data comes from FSRH clinical guidelines and pooled results from WHO clinical trials. Every source is listed at the bottom of the page. This page is for information only, so talk your options through with a GP, sexual health clinic or pharmacist.
DISCLAIMER: This website is for 18+ and does not provide medical advice. Read more here.
