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What are diaphragms or caps?

  • Diaphragms and caps are types of contraception you put inside your vagina before sex. You need to use them with spermicide (gel, foam or cream that kills sperm).
  • Diaphragms and caps are discs or small domes made of thin, soft silicone or latex. They cover the cervix (entrance to the womb).
  • They prevent pregnancy by stopping sperm entering the womb.
  • Diaphragms and caps are not suitable for everyone.
  • Caps are smaller than diaphragms and you can leave them in for longer.
  • If correctly used diaphragms and caps are estimated to be between 92 and 96% effective. If not used correctly they are less effective.
  • You can compare different methods, including how well they work and side effects, when choosing a method of contraception.
Information:

Diaphragms and caps do not stop you getting or passing on sexually transmitted infections (STIs). Use a condom every time you have sex to protect you and your partner against STIs including HIV.

Page last reviewed: 31 January 2024
Next review due: 31 January 2027