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Also known as the cap
The diaphragm is a small bowl-shaped dome made out of silicone or latex which fits inside the vagina, making a barrier between the vagina and the cervix. Diaphragms are always used with spermicide, a chemical gel or foam that kills sperm.
The diaphragm creates 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, with spermicide, can be put in up to 3 hours before sex, but must not be removed sooner than 6-8 hours after sex.
When fitted correctly and used with spermicide the diaphragm is between 92-96% effective in preventing pregnancy.
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.
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.
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 sexually transmitted infections like a condom does.
The diaphragm is available free on the NHS. You can only get it on prescription from a doctor. This can be your GP, another GP who you have registered with for family planning services, or a doctor at a family planning or young person’s clinic.
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