6 common condom mistakes that can significantly increase your chances of pregnancy

• Male condoms are 98% effective with perfect use and 85% effective with typical use.
• Female condoms are slightly less effective - 95% with perfect use and 79% typically.
• People make mistakes with condoms like not checking the expiration or using the same one twice.

Condoms can be a great way to prevent pregnancy and guard against sexually transmitted infections. In a 2015 survey, 24% of women and 34% of men in the US between ages 15 and 44 said they used an external or male condom the last time they had sex.

But condoms don't always work perfectly - they can break or slip off during sex, putting you at risk for getting pregnant.

Note: Throughout this piece condoms may refer to the popular male condom that fits over a penis. But it could also refer to less common female condoms. If neither is specified, you may assume it applies to both types.

Here are a few tips to follow to make sure you're using condoms correctly.

How effective are condoms?

If you use them perfectly, external or male condoms can prevent pregnancy 98% of the time. But in reality, people make mistakes, and with typical use, condoms actually prevent pregnancy about 85% of the time. This means that 15 out of every 100 people who use condoms as their only form of birth control for a year, will become pregnant.

Internal or female condoms fit inside the vagina rather than over the penis. They are much less widely available and slightly less effective than external condoms. With perfect use, they work 95% of the time, and with typical use, they're 79% effective.

There are a lot of easy missteps you can make when using condoms which will increase your risk of pregnancy, says Christine Greves, MD, an OB-GYN at Winnie Palmer Hospital for Women & Babies. Some of the most common mistakes are:

• The male condom can slip off of the penis during sex.
• Male condoms can break inside of the vagina
• If you're using a female condom, the penis can slip between the condom and the vaginal wall.
• Storing condoms in a hot environment like your pocket or a hot car can make the latex weaker and more likely to break.

Note: Never use an expired condom, since it's more likely to break. Each condom will have an expiration date printed on the individual wrapping. Latex condoms are usually good for about five years, whereas lambskin condoms last about three years.

How to use condoms

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Condoms are most effective if you use them properly. Frances Casey, MD, MPH, a professor of obstetrics and gynecology at Virginia Commonwealth University, recommends the following steps for how to use both male and female condoms correctly:

How to use male condoms

1. Remove the condom from the package and check for any damage like visible holes or tears.
2. Place it at the top of the erect penis and make sure that it can roll downward along the shaft (if you cannot roll the condom down, it may be inside out). If you have foreskin, pull it back before putting on the condom.
3. Pinch air out of the tip and roll the condom down to the base of the penis.
4. After sex, grip the condom at the base and pull the penis out of the vagina or anus. Don't pull out without gripping the condom as it can slip off the penis, making the contents spill into the vagina or anus, which could lead to pregnancy or a sexually transmitted infection.

How to use female condoms

1. Remove the condom from the package and check for any damage like visible holes or tears.
2. To insert the condom, squeeze the ring at the closed end and insert it the same way you'd put a tampon into the vagina. You can put the condom in place for up to eight hours before sex.
3. Push the ring as far into the vagina as it can go. Do not let it twist.
4. The outer ring of the female condom should stay outside of the vagina, covering the vaginal opening about an inch past the labia.
5. Guide the penis into the opening of the female condom. Stop having sex if you feel the penis slip between the condom and vaginal walls or if the outer ring moves into the vagina.
6. Remove by gently twisting the condom out of the vagina.

How to avoid common condom mistakes

Greves offers a few pieces of advice to make sure you're using condoms the right way:

1. Mistake 1: Using multiple condoms at once: Don't use multiple condoms at the same time, as this can create friction and cause a break.
2. Mistake 2: Storing condoms in hot environments: Make sure that external condoms are properly stored in a cool environment. Never use a condom that has been exposed to temperatures over 104 degrees Fahrenheit. However, note that internal female condoms are generally made from polyurethane or synthetic latex, which aren't affected by heat.
3. Mistake 3: Ripping the condom when you open its wrapper: When opening a condom wrapper, open along the recommended area and don't use your teeth or fingernails, as this can cause a tear.
4. Mistake 4: Using a questionable condom: Check condoms for damage before using them. "If the condom is sticky, brittle, discolored, or damaged it should not be used," Casey says.
5. Mistake 5: Using the wrong lube: Only use water or silicone-based lubricant with condoms. Lubricants that contain oil can break down latex.
6. Mistake 6: Reusing condoms: Don't reuse an external or internal condom if you want to go for a second round, and if you have sex for longer than 30 minutes, put on a new condom. Too much heat and friction can weaken the material.

Insider's takeaway

Condoms work well to prevent pregnancy, but only if you use them correctly. It's important to follow all the proper steps and avoid mistakes like leaving them in a hot car or using an oil-based lubricant.

If you have sex often, you may want to use a backup contraception method like the pill. And if you have a new partner or are seeing multiple people, "it's best for both partners to have a lab panel done to check for sexually transmitted infections," Greves says.

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