Why are condoms not 100% effective?
Hello I would like to understand a few things, starting with the real risk of HIV considering the following:
1. Proper use of condom.
2. condom didn’t break or slipped
3. Penetration lasted less than 90 seconds
4. Other person claims to be clean but have no way of verifying
5. I am circumcised
Why are condoms not 100% effective? Is it because there is a chance of it breaking or people not using it properly? If a condom is properly used then it should be effective?
I am aware that the risk per unprotected exposure for vaginal sex is 0.04% around 4 in 10000 exposures, and that circumcision decreases risk 50-60% and use of condoms is 98% effective, so how does the cumulative risk work? If exposure unprotected is 0.04 and circumcision lowers that by 50-60% and condom decreases by 98% then what is the real risk?
Hi
. It is clear and understandable that you have concerns about individual risk. The stats that you mention are useful in understanding risk and mitigating it, but it is important to note that they are derived from compilation of a significant amount of data. Every individual case has numerous unique circumstances that make being precise about specific risk impossible. I want to call your attention to this article from our editorial team on differences in HIV transmission risk, specifically the section near the bottom on factors that can change risk estimates: https://h-i-v.net/transmission-risks. An example is, as you mentioned, the use of condoms and the corresponding reduction of risk. This can be impacted by misuse, breakage, or as noted in this article on risk reduction, even the type of lubricant used: https://h-i-v.net/risk-reduction. The scenario you describe points to a low risk, but the only way to ever be sure is testing (see here for more information: https://h-i-v.net/diagnosis-testing), which is why the CDC recommends that testing for sexually transmitted infections should be a regular part of health maintenance. I hope this information is helpful and please know that this people here understand and that this community is here for you. Best, Richard (Team Member) 
Alafia (Peace) We are not medical experts so I don't want to speculate about your actual risk. I will share my belief that your risk is extremely low. Khafre (H-I-V.net Team Member)
