A diaphragm is a dome made of soft silicone. You insert it into your vagina before sex to cover the cervix, so that sperm cannot get into the womb. You need to use spermicide with it, which kills the sperm. They are useful for people who do not want to use a hormonal or long lasting contraceptive.

The diaphragm can be purchased from pharmacies. It comes in one size only and therefore does not need to be fitted by a health professional. However, you may wish to visit your local sexual health clinic to discuss how you should fit it.

When used correctly they are between 92-96% effective at preventing pregnancy.

How it works

How to use it

With clean hands, put a small amount of spermicide on each side of the diaphragm. Slide the diaphragm into your vagina, and push it far enough in that it covers your cervix.

You will need to leave the diaphragm in for at least 6 hours after sex.

What it does

The diaphragm stops sperm from reaching an egg by covering your cervix, while the spermicide kills any sperm in the vagina.

Pros and Cons


  • It can be put in before sex (but you will need to add extra spermicide if you have sex more than three hours after putting it in).
  • It is not affected by any medicines that you take in tablet/oral form.
  • It can be used by people who can't use hormonal contraception.
  • It doesn't disturb your menstrual cycle.


  • It doesn't protect you against STIs.
  • It can take a little getting used to before you’re confident using it.
  • Some people may be sensitive to latex or the chemical used in spermicide.
  • They aren’t as effective as other methods of contraception.
  • Some people can develop the bladder infection cystitis when using diaphragms.
  • It is recommended that you do not use the diaphragm/cap during your period, so you will need to use an alternative method of contraception at this time.

How to use a diaphragm

Before use, check your diaphragm regularly for tears or holes by holding it up to the light and having a good look at it. Be careful with your fingernails and jewellery. If your diaphragm goes out of shape, squeeze it gently back into its circular shape.

Your diaphragm may become discoloured. Don’t worry; this will not make it less effective.

  • You can insert a diaphragm up to two hours before you have sex – after this time, you will need to take it out and put some more spermicide on it, or use an applicator to apply more spermicide.
  • With clean hands, put a small amount of spermicide on each side of the diaphragm (also putting a little spermicide on the rim may make the diaphragm easier to put in).
  • Put your index finger on top of the diaphragm and squeeze it between your thumb and other fingers.
  • Slide the diaphragm into your vagina, upwards. This should ensure that the diaphragm covers your cervix.
  • Always check that your cervix is covered – it feels like a lump, a bit like the end of your nose.
  • If your cervix is not covered, take the diaphragm out by hooking your finger under the rim or loop (if there is one) and pulling downwards, then try again.
  • You must leave it in for at least six hours after the last time you had sex. You can leave it in longer but do not exceed 24 hours.

After use, you can wash your diaphragm with warm water and mild, unperfumed soap. Rinse it thoroughly, then leave to dry. You will be given a small container for it, which you should keep in a cool, dry place.

Never boil your diaphragm, never use disinfectant or detergent to clean it or use talcum powder with it.


Where can i get it?

You can buy diaphragms from pharmacies and some online stores.

Who is the diaphragm not suitable for?

The diaphragm may not be suitable if you:

  • Have an unusually shaped or positioned cervix (entrance to the womb), or if you cannot reach your cervix.
  • Have weakened vaginal muscles (possibly as a result of giving birth) that cannot hold a diaphragm in place.
  • Have a sensitivity or an allergy to the chemicals in spermicide.
  • Have ever had toxic shock syndrome (a rare, but life-threatening bacterial infection).
  • Have repeated urinary tract infections (an infection of the urinary system, such as the urethra, bladder or kidneys).
  • Currently have a vaginal infection (wait until your infection clears before using a diaphragm).
  • Are not comfortable touching your vagina.
  • Have a high risk of getting an STI – for example, if you have multiple sexual partners.

Where do I get spermicide from?

You can get spermicide from a pharmacy or your local sexual health clinic.

What can make the diaphragm less effective?

The diaphragm can become less effective at preventing pregnancy if:

  • It is damaged – for example, it is torn or has holes.
  • It is not the right size for you and doesn’t cover your cervix.
  • You use it without spermicide, or have sex three hours or more after you apply spermicide.
  • You do not use extra spermicide with your diaphragm every time you have more sex.
  • You remove it too soon (less than six hours after the last time you had sex).
  • You use oil-based products, such as baby lotion, bath oils, moisturiser or some vaginal medicines (for example, pessaries).

If any of these things happen, or you have had sex without contraception, you may need emergency contraception.

What should I expect if I go to get a diaphragm?
  • A doctor or nurse will explain how to put in and take out the diaphragm and use spermicide.
  • They will ensure you can insert and remove your diaphragm independently before you leave the clinic.
  • You will only need to see a doctor or nurse to replace it or if you have any questions or concerns.