Diaphragm or Cap

Soft, flexible latex or silicone dome/cup shaped devices that fit in the vagina and cover the cervix (entrance to the womb). Caps are usually smaller.
They should be used with a spermicide.

Act as a barrier preventing sperm from entering the womb thereby stopping fertilisation with an egg.
The spermicide kills the sperm.

Quite effective – up to 6 out of 100 women will become pregnant each year if they are used perfectly and consistently. If not used perfectly more women will become pregnant (12 in 100)
You can insert the diaphragm ahead of time (up to three hours before sex) so that it doesn't interrupt sex.
Contains no hormones so no side effects and your period is not affected.
You only have to use it when you have sex.

Can “interrupt the mood” during sex if it’s not put in beforehand.
You should leave it in for at least 6 hours after the last time you had sex.
Extra spermicide is needed if you have sex again.
Spermicide can be messy.
They are less effective than most methods but better than using nothing. They fail because: device is damaged e.g. torn/has hole; wrong size; doesn’t cover the cervix; spermicide not used consistently; device is removed too soon; use of oil based lubricants which damage the latex.
No protection against sexually transmitted infections (STIs) – condoms advised.
If your body changes in certain ways, you might need a different size diaphragm.
The diaphragm cannot be used when you have your period.
The latex or spermicide can cause irritation of the penis or vagina and cystitis.
Can take time to learn how to use it.