27th June 2023

Barrier Methods

Male and female condoms provide a physical barrier to ejaculate, pre-ejaculate and cervicovaginal secretions entering the uterus. Fertilisation is prevented and the risk of transmission of sexually transmitted infections (STIs) is greatly reduced. No fitting is required (unlike other barrier methods) but care should be taken to ensure the patient is aware of the risks of failure. In practice, this is 18% for male condoms, meaning 18 in 100 women relying solely on this method of contraception will conceive within the first year, and 21% for female condoms.

Diaphragms and cervical caps both prevent sperm from reaching the cervix but do not prevent direct contact between the penis and vagina and so do not offer the same protection against STIs. Both diaphragms and caps need fitting, including resizing after childbirth due to the change in the cervix, and should be used in conjunction with spermicide (a chemical barrier to sperm entering the cervix). Failure rates for both when used in practice are at least 12%.