How effective condoms are, and where their protection has limits. The chapter explains that consistent, correct use can greatly reduce the risk of HIV and other STIs passed on through body fluids, such as chlamydia and gonorrhoea, drawing on clinical treatment guidelines. It also points out that condoms are less protective against infections spread through skin-to-skin contact. On pregnancy, it compares effectiveness with correct use against typical use, using figures from the UK National Health Service, to show how much difference using them properly makes. The result is a clear picture of what condoms can and cannot do for your sexual health.