What is the effectiveness of condoms in preventing pregnancy and STIs (Sexually Transmitted Infections)?

Condom Effectiveness for Preventing Pregnancy and STIs

When used consistently and correctly, condoms are very effective in preventing pregnancy and a variety of sexually transmitted infections (STIs), including HIV, with consistent and correct use reducing the odds of acquiring non-viral STIs by approximately 59%. 1

Effectiveness Rates

Pregnancy Prevention

• Male condoms have a failure rate of ≤2 per 100 condoms when tested for manufacturing defects 2
• Female condoms have a higher failure rate, with an estimated 12-month pregnancy prevention failure rate of 26% 2
• When used consistently and correctly, condoms can provide pregnancy protection similar to many hormonal methods 3

STI Prevention

• Condoms are highly effective against STIs transmitted between mucosal surfaces (HIV, gonorrhea, chlamydia) 4
• Less effective against STIs transmitted by skin-to-skin contact (like syphilis) where lesions may be outside the area covered by condoms 4
• Consistent and correct condom use reduces odds of acquiring non-viral STIs by 59% compared to non-use 1

Factors Affecting Effectiveness

Consistency of Use

• Consistent use (using a condom for every sexual encounter) is crucial for maximum protection 4
• Inconsistent use significantly reduces overall effectiveness for both pregnancy and STI prevention 2

Correctness of Use

• Most condom failures result from incorrect use rather than product defects 2
• Proper application and use techniques are essential for effectiveness 1

Proper Condom Use Techniques

To maximize effectiveness, condoms must be used correctly:

• Use a new condom with each act of intercourse
• Handle carefully to avoid damage from fingernails, teeth, or sharp objects
• Put on after erection but before any genital contact
• Ensure no air is trapped in the tip
• Use adequate lubrication during intercourse
• Use only water-based lubricants with latex condoms (oil-based lubricants weaken latex)
• Hold firmly at the base during withdrawal while penis is still erect 2

Limitations and Considerations

• Condoms do not cover all potentially infectious areas, particularly for skin-to-skin transmitted STIs 4
• No protection method is 100% effective 4
• Non-barrier contraceptive methods (hormonal contraception, IUDs, sterilization) offer no protection against STIs 2
• For individuals at high risk for both pregnancy and STIs, using both a hormonal method and condoms provides optimal protection 5

Condom Types and Accessibility

• Male condoms are generally easy to access at low cost and require no prescription 3
• Female condoms are more expensive and less accessible but offer the advantage of being female-initiated 3
• Recent advances in condom technology have improved quality and acceptability 3

Common Pitfalls to Avoid

• Using oil-based lubricants with latex condoms, which can cause condom degradation
• Not using condoms consistently for every sexual encounter
• Incorrect application (not leaving space at the tip, not unrolling completely)
• Not holding the condom during withdrawal, which can lead to slippage
• Assuming non-barrier contraceptives provide STI protection 2

Condoms remain one of the most cost-effective interventions for preventing both unintended pregnancy and STIs, with estimates showing that scaling up condom use could avert 240 million disability-adjusted life years (DALYs) by 2030 6.