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Dr. Chrysoula I. Liakou MD, PhD
- Treated online: Yes, usually. A doctor can advise on choosing and using a diaphragm or cap by video; sizing and fitting checks are in person.
- How well it works: a diaphragm used perfectly with spermicide is about 94% effective; with typical use, about 12 to 17 in 100 users become pregnant in a year.
- How to use it: put it in before sex with spermicide, and leave it in for at least 6 hours afterwards.
- No hormones: it suits people who want or need to avoid hormones, and it is only in place when you need it.
- Emergency: call 112 for a sudden high temperature with a rash, vomiting, dizziness or fainting while using a diaphragm or cap, which can be toxic shock syndrome.
Remove the diaphragm or cap and call 112 if you suddenly feel very unwell with a high temperature, a rash like sunburn, vomiting, diarrhoea, dizziness or fainting while using it. If it moved or came out during sex, emergency contraception works best the sooner it is taken.
Can an online doctor help with a diaphragm or cap?
Yes, usually. Choosing and using a diaphragm or cap is mostly about advice: whether it suits you, how to use it with spermicide, and what to do when something goes wrong. A doctor can go through this by video and arrange emergency contraception after a failure. A sized diaphragm or a cap needs to be fitted and checked by a trained nurse or doctor in person, and the doctor tells you where.
How an online consultation helps with a diaphragm or cap
- Is it right for you?: How effective it is compared with other methods, and whether your health and plans suit a barrier method.
- Using it well: When to put it in, how long to leave it, spermicide, and how to check the fit.
- Problems sorted: Cystitis, irritation, discomfort for either partner, or a diaphragm that keeps moving.
- After a failure: Emergency contraception, and whether another method would protect you better.
What the doctor checks in an online consultation about a diaphragm or cap
The doctor asks about any warning signs first, then about your health and how you use it. The doctor asks about:
- Warning signs: a high temperature with a rash or vomiting, pain, or unusual discharge while using it.
- How important avoiding pregnancy is: a barrier method is less effective than most other methods.
- Your health: a history of toxic shock syndrome, latex or spermicide allergy, prolapse, repeated cystitis, and your risk of HIV.
- Changes in your body: a recent birth, miscarriage or abortion, and any weight change of more than 3 kg, which can change the size you need.
- How you use it: timing, spermicide, and any times it moved or came out.
Before the call, have the diaphragm’s leaflet to hand, so the doctor can see the type and the time limits for your device.
What is a contraceptive diaphragm or cap, and how does it work?
A diaphragm is a soft, dome-shaped barrier of silicone or latex that you put into the vagina before sex so that it covers the cervix, the entrance to the womb. A cap is smaller and fits more closely over the cervix. Both stop sperm reaching an egg, and both are used with spermicide, a gel or cream that kills or stops sperm. Neither contains hormones.
- Sized diaphragms and caps: a trained nurse or doctor fits you for the right size, and checks it again after a birth or a weight change.
- Single-size diaphragm: a silicone diaphragm designed to fit about 8 in 10 women, which can be bought without a fitting, although it does not suit everyone.
- Replacement: a diaphragm or cap is usually replaced every year.
How effective is a diaphragm?
Less effective than most other methods. A diaphragm used perfectly with spermicide fails for about 6 in 100 users a year; with typical use, between about 12 and 17 in 100 become pregnant. Caps work less well after you have had a baby:
Swipe sideways to compare →
| Method | Perfect use | Typical use |
|---|---|---|
| Diaphragm with spermicide | About 6 in 100 | About 12 to 17 in 100 |
| Cap, if you have not had a baby | About 9 in 100 | About 12 in 100 |
| Cap, if you have had a baby | About 20 in 100 | About 24 in 100 |
| Spermicide on its own | About 19 in 100 | About 28 in 100 |
| External (male) condom | About 2 in 100 | About 13 to 18 in 100 |
| Internal (female) condom | About 5 in 100 | About 21 in 100 |
For comparison, fewer than 1 in 100 users of the implant or a coil become pregnant in a year.
How do you use a diaphragm or cap?
- Put spermicide on the diaphragm or cap as the leaflet shows.
- Put it in before sex: up to 2 hours before for a diaphragm, and check it covers your cervix.
- If you have sex again, add more spermicide without taking it out.
- Leave it in for at least 6 hours after the last time you had sex.
- Take it out within the time limit on the leaflet: usually up to 24 to 30 hours for a diaphragm and 48 hours for a cap.
- Wash it, let it dry, check it for holes or tears, and store it in its case.
Do diaphragms stay in all the time?
No. A diaphragm is put in before sex and taken out after at least 6 hours, within the leaflet’s time limit. Leaving it in for longer than that is linked to infection, including the rare toxic shock syndrome.
Can a partner feel a diaphragm during sex?
A diaphragm that fits well sits over the cervix and should not be uncomfortable for either of you. If either partner can feel it, or it causes pain, it may be the wrong size or in the wrong position, so get the fit checked.
What is spermicide, and do condoms contain it?
Spermicide is a gel or cream that kills or disables sperm. Most contain nonoxinol-9. It is used with a diaphragm or cap; on its own it is one of the least effective methods, with about 28 in 100 users becoming pregnant in a year.
- Condoms are no longer lubricated with spermicide, and condoms with nonoxinol-9 are not recommended.
- Used often, spermicide can irritate the vagina and cause small sores, which may make it easier to catch HIV.
- Spermicide does not protect against sexually transmitted infections.
Who should not use a diaphragm or cap, and the disadvantages
A diaphragm or cap is usually not recommended if you have a high risk of HIV, have had toxic shock syndrome, or are allergic to latex or spermicide, although a silicone diaphragm avoids latex. A prolapse, the shape of the vagina or cervix, or finding it hard to put in and take out can also make it unsuitable.
Swipe sideways to compare →
| Pros | Cons |
|---|---|
| No hormones and no lasting side effects | Less effective than most other methods |
| You only use it when you need it | Needs planning before sex, and spermicide |
| Can be put in up to 2 hours before sex | Can increase the risk of cystitis |
| No effect on fertility | Sized types need fitting, and refitting after a birth or weight change |
| Under your control | No reliable protection against sexually transmitted infections |
Why do fewer people use diaphragms now?
Mainly because other methods are more effective and need no planning around sex: with typical use, about 12 to 17 in 100 diaphragm users become pregnant in a year, compared with fewer than 1 in 100 with the implant or a coil. A diaphragm still suits people who want a hormone-free method they control and would accept a higher chance of pregnancy.
What might the doctor recommend about a diaphragm or cap?
This is the framework the doctors use:
Swipe sideways to compare →
| What you have | Likely first step | Suitable for online care? | When in-person care is needed |
|---|---|---|---|
| You want a hormone-free method you control | A comparison with the copper coil and condoms, and how to use a diaphragm | Yes | For sizing, if you choose a sized diaphragm or a cap |
| A diaphragm moved or came out during sex | Emergency contraception as soon as possible | Yes | If a copper IUD is the best option |
| Cystitis that keeps coming back | Treatment, emptying your bladder before and after sex, and a fit check | Yes | To check the size or try another type |
| Irritation or soreness | A check for spermicide or latex irritation, or an infection | Partly | If an examination is needed |
| A recent birth, or weight change of more than 3 kg | A refitting | Partly | For the refitting, from 6 weeks after a birth |
| High temperature, rash and vomiting while using it | Emergency care | No | Remove it and call 112 now |
Not sure whether a diaphragm or cap is right for you? A doctor can tell you in one consultation.
See available times →Diaphragm and cap: practical steps and options
What you can do yourself
- Practise putting it in and taking it out before relying on it, and check it covers your cervix every time.
- Keep spermicide with your diaphragm, and use a new application each time you have sex again.
- Empty your bladder before and after sex, which helps if you get cystitis.
- Replace it every year, and sooner if it is damaged.
- Use condoms as well if you need protection against sexually transmitted infections.
Prescription treatment
A prescription is never issued without a consultation. The doctor may prescribe emergency contraception after a failure, treatment for cystitis, or another method if a diaphragm turns out not to suit you, and tells you where a sized diaphragm or cap can be fitted. If the doctor prescribes, use the prescription at a pharmacy near you.
What does not help
Using oil-based products with a latex diaphragm, which can damage it. Taking it out too soon after sex. Relying on a diaphragm that no longer fits after a birth or a weight change.
Special situations
After a birth
A diaphragm or cap is not recommended in the first 6 weeks after a birth, because the vagina and cervix change shape. Your size needs checking again after a birth, a miscarriage or an abortion.
Over 40
A diaphragm can be used at any age, but a prolapse can make it harder to use and less reliable. The contraception in perimenopause page explains the other options.
Hormone-free choices
If you want to avoid hormones, the non-hormonal contraception page compares the diaphragm with the copper coil, condoms and fertility awareness.
Children
Mobi Doctor consultations are for adults aged 18 and over. A child who is unwell needs a paediatrician or a local doctor in person, and emergency signs in a child mean 112.
When a diaphragm or cap is handled online, and when you need in-person care
Handled online: choosing a method, how to use a diaphragm or cap and spermicide, cystitis and irritation, emergency contraception after a failure, and switching to another method.
In-person care: sizing and fitting a sized diaphragm or a cap, refitting after a birth or weight change, examinations, and any signs of toxic shock syndrome.
When to get in-person care
Call 112 or go to an emergency department now for:
- a sudden high temperature with a rash like sunburn, vomiting, diarrhoea, dizziness or fainting while using a diaphragm or cap
- swelling of the lips, face or throat, or difficulty breathing, after using latex or spermicide
Get medical advice the same day for:
- a diaphragm or cap that moved or came out during sex, for emergency contraception
- burning when you pee, or needing to pee often, with a high temperature or pain in your back or side
- pain or bleeding when using the diaphragm
- a diaphragm or cap you cannot remove
How Mobi Doctor works
- Book a time that suits you: daily 7am–11pm CEST. You can see a doctor over video, usually within 15 minutes. No subscription, and the exact price is shown before you pay.
- Speak to a licensed doctor about the diaphragm: say what you want from contraception, how you use the diaphragm or cap, and any problems you have had.
- Leave with a plan: what to do, what to take and for how long, and which signs mean you should be seen in person. If the doctor prescribes, use the prescription at a pharmacy near you.
No sign-up needed
Noticed a new symptom when using a diaphragm or cap? Tick every symptom you have to see each condition page that mentions it. It finds the right page, not a diagnosis: a doctor gives you that on a video call.
Tap the body — an area or a point — to browse symptoms anywhere
Similar symptoms, different condition? Female Condoms can start the same way. Compare them, or look up any other symptom in the full symptom checker.
Frequently asked questions about the diaphragm and cap
What is a contraceptive diaphragm?
A diaphragm is a soft, dome-shaped barrier of silicone or latex that you put into the vagina before sex so that it covers the cervix. It is used with spermicide and contains no hormones.
How does the diaphragm work?
A diaphragm covers the cervix so that sperm cannot get into the womb, and the spermicide kills or stops sperm. You put it in before sex and leave it in for at least 6 hours afterwards.
How effective is a diaphragm?
Used perfectly with spermicide, about 6 in 100 diaphragm users become pregnant in a year. With typical use, it is between about 12 and 17 in 100, much higher than with the implant or a coil.
Do diaphragms stay in all the time?
No. A diaphragm goes in before sex and comes out after at least 6 hours, within the time limit on the leaflet, usually up to 24 to 30 hours. Leaving it in longer is linked to infection.
Can a man feel the diaphragm during sex?
A diaphragm that fits well should not be uncomfortable for either partner. If either of you can feel it, or it causes pain, it may be the wrong size or in the wrong position, so get the fit checked.
What are the disadvantages of using a diaphragm?
A diaphragm is less effective than most other methods, needs planning and spermicide, can increase the risk of cystitis, needs refitting after a birth or weight change, and does not reliably protect against sexually transmitted infections.
How can I prevent cystitis when using a diaphragm?
A diaphragm presses on the urethra and bladder, which is why cystitis is more common with it. Make sure the fit is right, since one that is too large presses harder; empty your bladder before and after sex; drink enough fluid; and take it out as soon as 6 hours have passed. If you keep getting cystitis, a smaller size, a cap, or a different method usually solves it, so ask a doctor for a fitting check.
What is spermicide?
A gel or cream, most often containing nonoxinol-9, that kills or disables sperm. It is used with a diaphragm or cap. On its own, about 28 in 100 users become pregnant in a year.
Do condoms have spermicide?
Condoms are no longer lubricated with spermicide, and condoms with nonoxinol-9 are not recommended, because frequent use can irritate the vagina and may make it easier to catch HIV.
Why do fewer people use diaphragms now?
Because other methods, such as the implant and coils, are much more effective and need no planning around sex. A diaphragm still suits people who want a hormone-free method they control.
Do I need to be fitted for a diaphragm?
For a sized diaphragm or a cap, yes, by a trained nurse or doctor, and again after a birth or a weight change of more than 3 kg. A single-size silicone diaphragm fits about 8 in 10 women without fitting, but not everyone.
How long does a diaphragm last, and how do I look after it?
A silicone diaphragm or cap can last up to about 2 years, following the maker's leaflet, but check it for holes, tears or thinning every time you use it. After each use, wash it with warm water and mild soap, let it dry and store it in its case; never use oil-based products on it. You need a fitting check, and often a new one, after a birth, a miscarriage or an abortion, or if you gain or lose more than 3 kg.
Can an online doctor help with a diaphragm?
Yes. A doctor can help you decide whether a diaphragm or cap suits you, explain how to use it, sort out problems such as cystitis, and arrange emergency contraception after a failure. Sizing is done in person.
- Female barrier methods of contraception, Patient.info, professional reference, Tidy C, updated 15 August 2023.
- Barrier and other pericoital contraceptives, MSD Manual Professional Version, Casey FE, reviewed December 2025.
- Diaphragm, Contraception Choices, College of Sexual and Reproductive Healthcare (UK), accessed 15 October 2026.
- Diaphragm or cap: side effects and risks, NHS, National Health Service (UK), reviewed 31 January 2024.
- Which methods are best at preventing pregnancy?, Contraception Choices, College of Sexual and Reproductive Healthcare (UK), accessed 15 October 2026.
- FSRH Clinical Guideline: Emergency Contraception, Faculty of Sexual and Reproductive Healthcare (now the College of Sexual and Reproductive Healthcare), March 2017, amended July 2023.
This page is for information only and is not a substitute for a medical consultation. Guideline links are provided for transparency; treatment decisions are made with your doctor.
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