Diaphragms and caps

Both the diaphragm and the cap work by stopping sperm from entering the womb by covering the cervix. You also need to use a spermicide with the diaphragm/cap. Spermicide gel contains chemicals that kill sperm.

You only need to use diaphragms and caps when you have sex, and you must leave then in for at least six hours afterwards.

Diaphragms and caps must be fitted by a trained doctor or nurse on the first occasion. They may not be available at your local clinic, so it is best to contact the clinic to check first.

You can get diaphragms and caps from Brook services, contraception clinics, GUM clinics and some GP surgeries. Use our find a service tool to find places near you.

Contraception and sexual health services such as Brook are free and confidential, including for people under the age of 16. Health professionals work to strict guidelines and won’t tell anyone else about your visit unless they believe you’re at serious risk of immediate harm. Find out more about Brook’s confidentiality policy.

When you go to get the diaphragm or cap, an appointment will typically include:

• A few questions about your medical and family history, to work out what would suit you best
• A doctor or nurse will examine you and recommend the size or shape to suit you
• They will show you:
  • how to insert the diaphragm or cap
  • how to use spermicide
  • how to take the diaphragm or cap out

Initially you may be fitted with a temporary ‘practice’ diaphragm or cap so that you can learn how to use it and see how it feels. During this time you will not be protected from pregnancy  so will need to use additional contraception such as condoms. When you go back you should wear the diaphragm or cap so that the doctor or nurse can check it is the right size.

Once you have had the diaphragm or cap fitted, you will only need to go back to the doctor or nurse to replace it (most people can use the same one for a year). 

You may also need to get a different size diaphragm or cap fitted if you gain or lose more than 3kg (7lb) in weight, or if you have a baby, miscarriage or abortion.

You can put the diaphragm in before you have sex but if you put it in more than three hours before you will need to use extra spermicide. You should avoid using diaphragms or caps during your period because of the possible risk of toxic shock syndrome.

Putting diaphragms in:

1. Find a position that’s comfortable for you, and with clean hands, put a small amount of spermicide on the upper surface of the diaphragm (some women find that putting a little spermicide on the rim makes the diaphragm easier to put in)
2. Put your index finger on top of the diaphragm and squeeze it between your thumb and other fingers.
3. Slide the diaphragm into your vagina upwards and backwards
4. Always check that your cervix is covered (it feels like a lump 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 and try again
5. You can insert a diaphragm up to three hours before you have sex, after this time you will need to take it out and put more spermicide on it

Putting caps in:

1. Fill one-third of the cap with spermicide, but don’t put any spermicide around the rim as this will stop the cap from staying in place. The silicone cap also has a groove between the dome and the rim and some spermicide should be placed there too
2. Find a position that’s comfortable for you and squeeze the sides of the cap together, holding it between your thumb and first two fingers.
3. Slide the cap into your vagina upwards and backwards
4. The cap must fit neatly over your cervix and it stays in place by suction. Always check that your cervix is covered. Depending on the type of cap, you may need to add extra spermicide after it has been put in
5. You can insert a cap up to three hours before you have sex – after this time, you will need to take it out and put some more spermicide on it

How to take out diaphragms or caps:

You can leave it for longer, but not for more than the recommended maximum time (including the minimum six hours):

• 30 hours for latex types
• 48 hours for the silicone cap