You only have to use a diaphragm or cap when you have sex, but you must leave it in for at least 6 hours after the last time you had sex. You can leave it in for longer than this, but don’t take it out before.
You need to apply more spermicide if:
- you have sex again with the diaphragm or cap in place
the diaphragm or cap has been in place for three hours or more before you have sex
- Don’t take the diaphragm or cap out to reapply spermicide.
You shouldn’t use a diaphragm or cap during your period as there is a possible link with toxic shock syndrome (TSS), a rare condition that can be life threatening.
Most women are able to use a diaphragm or cap, but it may not be suitable for you if you:
- have an unusually shaped or positioned cervix (entrance to the womb), or if you can’t reach your cervix
- have weakened vaginal muscles (possibly as a result of giving birth) that can’t hold a diaphragm in place
- have a sensitivity or an allergy to latex or the chemicals in spermicide
- have ever had toxic shock syndrome
- have repeated urinary tract infections
- currently have a vaginal infection (wait until your infection clears before using a diaphragm or cap)
aren’t comfortable touching your vagina
- have a high risk of getting an STI – for example, if you have multiple sexual partners
Research shows spermicides that contain the chemical nonoxynol-9 don’t protect against STIs, and may even increase your risk of getting an infection.
A diaphragm or cap may be less effective if:
- it’s damaged – for example, it’s torn or has holes
- it’s not the right size for you
- you use it without spermicide
- you don’t use extra spermicide with your diaphragm or cap every time you have more sex
- you remove it too soon (less than 6 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) with latex diaphragms – these can damage the latex
If any of these things happen or you’ve had sex without contraception, you may need to use emergency contraception.