Last updated on August 18, 2020
What is the chance of a woman becoming pregnant if a condom slips off?
If a married couple regularly had sex with no contraceptive, in one year they would have an 85% chance of pregnancy. A failed condom basically places the odds equal to no protection at all.
Studies vary, but latex condoms slip off somewhere between 0.6% and 1.3% of the time. [Scientific Evidence on Condom Effectiveness for Sexually Transmitted Disease (STD) Prevention, July 20, 2001] Polyurethane condoms have a worse average, slipping off about 3.6% of the time. [Breakage and Acceptability of a Polyurethane Condom, Family Planning Perspectives, Vol. 30, No. 2, March/April 1998]. The latter study also noted that the odds for slippage are significantly higher for men who are younger than 25.
You didn’t ask about breakage rates, but these should be factored in as well. Again, the first study found that latex condoms break between 0.4% and 2.3% of the time. The second study found that polyurethane condoms broke 7.2% of the time. This gives a total failure rate for latex condoms to be somewhere between 1% and 3.6% of the time and for polyurethane condoms about 10.8% of the time.
It should be noted that there have been no reliable studies of condom failures when the users are younger than 18. However, given that users under 25 have had higher failure rates when compared to users over 25, it should cause young people to stop and think.
Therefore, when factoring in failures, you should expect to see regular users of latex condoms experience a pregnancy between 1 and 3 out of 100 couples in one year because of failures. Regular users of polyurethane condoms will have a pregnancy in 9 out of 100 couples in one year due to failures. The reality is that couples regularly using condoms see a 14% pregnancy rate in one year. The difference is usually explained as carelessness or mistakes caused by the users of the condoms.
To put this in perspective, how would you like to eat at a restaurant where only 14 out of 100 patrons get food poisoning in one year? Yet, that is the type of odds people are playing around with by having sex outside of marriage. They are trying to avoid the consequence of sin, but the consequences cannot be totally eliminated.