The diaphragm and cervical cap are small bowl-shaped domes made out of silicone or latex which fit inside the vagina and cover the cervix, making a barrier between the vagina and the cervix.
Diaphragms and caps are always used with spermicide, a chemical gel or foam that kills sperm
How does it work?
They create a barrier between the vagina and the cervix, preventing sperm from being able to travel into the womb and meet an egg. The spermicide used with the diaphragm also kills the sperm.
The diaphragm and cap, with spermicide, can be put in up to three hours before sex, but must not be removed sooner than six hours after sex.
How effective is it?
When fitted correctly and used with spermicide the diaphragm is between 92-96 per cent effective in preventing pregnancy.
What are the advantages?
It can be put in before sex and so does not interrupt things, and it has no health risks associated with it. It is also a non-hormonal method of contraception.
Some research suggests that using the diaphragm may provide some protection against cervical cancer, and some sexually transmitted infections.
What are the downsides?
It can take a while to get the knack of fitting it correctly, and you may find the spermicide messy. Also some people find spermicide irritates their skin, or that using the diaphragm causes cystitis.
It is also not as effective in preventing pregnancy as most other types of contraception available.
Things to bear in mind
If you gain or lose weight you diaphragm may not fit properly and will be less effective. If your weight changes it is important to see a doctor or nurse to get a new diaphragm
Most importantly, the diaphragm does not provide any protection against HIV although it may protect against some other sexually transmitted infections like a condom does.
Where can I get it from and how much does it cost?
The diaphragm is available free on the NHS. You can only get it on prescription. This can be from your GP, another GP who you have registered with for family planning services, a practice nurse or a family planning or young person's clinic.