What are the common reasons for condom failure?

Dear Ludek, 

Condoms are generally effective at protecting against pregnancy. However, they can be much less effective if you use an expired one, choose the wrong size, or put it on incorrectly. While pre-ejaculate (also known as pre-cum) is different from ejaculate, it may still carry sperm or sexually transmitted infections (STIs). Read on to learn more about why some condoms may fail, the risks pre-cum can carry, and what you can do to reduce yours or your partner’s risk of pregnancy.  

What are the common reasons for condom failure? 

A variety of reasons related to incorrect usage can make condoms more likely to break or not work as they’re designed to. Some of these reasons include:  

• The condom being expired or the incorrect size 
• Improper storage, including storing in heat and under direct sunlight; or in a high friction environment, such as keeping it in a wallet for a long time 
• Using oil-based lubricant which weakens the latex material 
• Wearing two condoms together (also known as double bagging) 
• Opening the package with sharp objects, such as with your teeth, which could unknowingly put a puncture in the package  
• Attempting to wear the condom inside out or forgetting to hold the tip to leave air when rolling it on 

List adapted from VeryWell Health and WebMD 

With typical use—which takes into account that people sometimes make mistakes or don’t use them perfectly—external condoms (worn on a penis) fail about 14 percent of the time, and internal condoms (used inside the vagina) fail about 21 percent of the time. These rates are much higher compared to the two percent failure rate when they’re used consistently and perfectly as instructed.  

Can pre-cum lead to pregnancy and other risks? 

The short answer is yes—there’s a chance that exposure to pre-cum can result in pregnancy or STIs. Pre-cum is a transparent and sticky liquid that comes out of the tip of the penis when someone is sexually aroused. It protects sperm from the acidic environment in both the urethra and the vagina. Pre-cum also provides lubrication during sexual intercourse.  

Pre-cum is different from ejaculate (also known as semen or cum). While pre-cum and cum are made in different parts of the reproductive track, both exit the body through the urethra. Pre-cum is not produced in the same place as sperm, so it typically doesn't contain sperm; however, it can sometimes pick up sperm left in the urethra and carry it out of the body. One reason this might happen is when pre-cum is exiting the body, it picks up sperm left in the urethra by a recent ejaculation. This makes getting pregnant from pre-cum possible and unpredictable. 

Besides pregnancy, pre-cum may also transmit STIs, like human immunodeficiency virus (HIV), chlamydia, gonorrhea, and hepatitis B. Therefore, using protection when there’s genital contact offers more reliable prevention, both from pregnancy and from STIs. 

How can you increase protection against pregnancy? 

While no studies have focused specifically on the risk of transferring pre-cum to condoms with hands, putting on and using condoms correctly may help lower the risk of both pregnancy and STIs. Additionally, making sure that condoms are not expired, are stored in a location with a moderate temperature, are the correct size for you or your partner, and using a water- or silicone-based lube are all things that can help reduce the risk of condom failure.  

You can also combine other form(s) of contraception with a condom to further lower the risk of getting pregnant if your condom does fail. By learning more about different birth control methods, you can make informed decisions based on your needs and preferences. 

Hopefully this response helped to break down the ins and outs of condom failure!