Why are condoms not 100 percent effective against pregnancy

• What Are Condoms?
  • What are condoms and how do they work?
• Effectiveness
  • Effectiveness of condoms
• Tips for Using
  • Tips for using condoms
• Other Forms of Birth Control
  • Other forms of birth control
• Condoms Protect Against HIV
  • Do condoms really protect against HIV?
• Condoms and HIV
  • Condoms and HIV
• Proper Condom Use
  • Proper condom use matters
• Internal Female Condoms
  • Internal or female condoms
• If You Are Exposed to HIV
  • If you have been exposed to HIV
• Related Resources
  • Related Resources - Should I Be Worried About Pregnancy if I Used a Condom?

Condoms are a popular method of birth control. If used correctly, there's about a 2 percent risk of becoming pregnant while using a condom, but it's a good idea to use another method of birth control along with it.

Condoms are a popular method of birth control since they are highly effective when it comes to preventing pregnancy and sexually transmitted diseases (STDs). They also don't contain any hormones. When condoms are used correctly, they have a very high rate of preventing pregnancy. Even so, they aren't 100% effective, so it's a good idea to use condoms along with another form of birth control to practice safe sex.

What are condoms and how do they work?

A condom is a barrier form of birth control that prevents you from directly touching your partner. This is the best way to protect both of you from STIs. It’s also an effective method of birth control since it stops the man’s sperm from reaching the woman’s eggs.

There are three different kinds of condoms:

• Male condom: goes over the penis and collects semen when the man ejaculates.
• Female condom: also called an internal condom, this kind goes inside the woman’s vagina to prevent sperm from reaching the eggs.
• Dental dam: a special condom you can use during oral sex to prevent STIs.

Condoms can be made of latex, polyurethane, or lambskin. Latex condoms are the best choice since they don’t break as easily and do a good job of preventing STIs. If you or your partner have a latex allergy, polyurethane condoms are the next best choice.

Some condoms are lubricated to reduce the friction created during sex. This helps to prevent the condom from breaking or tearing. Condoms may also be coated with spermicide, too. In case the condom does break, the spermicide can help slow the sperm down so it doesn't reach the egg.

Effectiveness of condoms

No method of birth control has a 100% rate of preventing pregnancy. However, if you use condoms correctly, there is a very good chance of preventing pregnancy. Condoms have a 98% rate of effectiveness, meaning there’s still a 2% chance that you could become pregnant while using a condom. This can happen if the condom breaks and you don’t use a secondary form of backup birth control. There is also a small chance that pre-ejaculate, or pre-cum, could reach the egg before the condom is put on properly.

If condoms are your only form of birth control, they must be used every time that you have sex in order to prevent pregnancy. It must be put on correctly, right side out. You should also only use condoms that aren’t expired. Old condoms tend to break easier.

If a condom breaks during sex, most people don’t realize it until after. If you realize during sex that the condom broke, you should stop right away and put on a new one. If you know the condom broke and it was your only form of birth control, there is a possibility of becoming pregnant. To avoid pregnancy, you can call your doctor or health care provider to seek out emergency contraception.

If you used a condom but are worried there might be a chance of becoming pregnant for any reason, you should wait to take a pregnancy test until at least one week after your missed period. If taken too early, a pregnancy test can give a false negative result.

Tips for using condoms

When you use condoms correctly, your chances of preventing pregnancy increase.

Storage. Keep your condoms somewhere that isn’t too hot or too cold. They should also be kept somewhere away from sharp objects or other items that could puncture the condom. This includes not carrying condoms in your wallet where they can easily get broken before use.

Lubricants. If you use lubricants, avoid oil-based products. These products, like lotions or Vaseline, can break down the latex in condoms. However, you can use oil-based lubricants with polyurethane condoms. To be safe, stick to water-based lubes since they are safe to use with any kind of condom.

Timing. When practicing safe sex, a condom must be put on before sexual contact begins. As mentioned, it is possible that you could get pregnant if pre-cum enters the vagina before a condom is worn. Don’t think of putting on a condom as an interruption. Instead, just think of it as part of the process.

Also, remember that a condom can only be worn once. If you have sex multiple times, it’s important to put on a new condom each time. 

Other forms of birth control

To fully prevent pregnancy, it’s important to use a backup form of birth control. For women, some hormonal options include:

• Oral contraceptive pills
• IUD (hormonal)
• Shot
• Implant
• Patch
• Vaginal ring

Some barrier methods include:

• Diaphragm (cervical cap)
• Sponge
• Spermicide (gel, foam, cream, depository)

Keep in mind that neither hormonal nor barrier methods are 100% effective against preventing pregnancy. Only condoms are effective at preventing STIs.

Even if you use a condom every time, knowing when you’re fertile and keeping track of when you have sex can help you better understand when you can get pregnant.

Do condoms really protect against HIV?

Condoms are, without doubt, the most effective means for preventing human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs), provided they are used in the right manner and during every sexual encounter.

HIV attacks the body’s immune system. About 37,968 people were diagnosed with HIV in the United States and dependent areas in 2018, causing the number of people with HIV to increase to about 1.2 million.

QUESTION

Condoms and HIV

Condoms, both female (internal condoms) and male (external condoms), are advocated as the best protection from HIV. They reduce the risk of HIV transmission by more than 90 percent if used consistently and the instructions are followed. They can be used during vaginal, anal and oral sex.

HIV can be transmitted through blood, semen, rectal and vaginal fluids. An intact latex condom, a polyurethane external condom (although they are more likely to break than latex condoms) or a polyurethane internal condom will not allow any of these fluids to pass through, thereby preventing the transmission. Animal skin condoms are not as effective as latex or polyurethane condoms in preventing HIV.

Proper condom use matters

For preventing HIV, not only the use of condoms but also their proper use matters. A few points must be considered when using external (or male) condoms for HIV prevention.

• Check the expiration/expiry date on the condom pack before use. Beyond the expiration/expiry date, condoms are more likely to become dry and crack.
• Store condoms away from light and heat to prevent them from drying or cracking.
• A latex condom is preferred because it is more effective in preventing HIV (and even pregnancy) than a polyurethane condom. If, however, you have a latex allergy, a polyurethane condom is a good alternative.
• Choose condoms with reservoir tips meant for catching semen after ejaculation.
• Condoms must be put on before any sexual contact. This is because HIV can be passed on through pre-cum, vaginal fluid and anal mucus.
• Open the condom pack carefully with your hand and not your teeth or scissors to avoid breaking or tearing the condom.
• Lightly pinch the tip of the condom (reservoir tip) and place it at the top of the penis. This helps remove trapped air at the top that may lead to condom breakage.
• Only use water-based or silicone-based lubricants while using a condom.
• Avoid using lotion, petroleum jelly and oil-based lubricant, including baby oil and massage oil, with condoms because they can cause condom breakage.
• Roll the condom down on the hard penis until it is completely rolled out. If you are uncircumcised, pull back the foreskin first.
• If you have placed it inside out by mistake, throw it away and use another condom. This is because some of the secretions may be passed on the other surface of the condom that comes in contact with the vagina or anal or oral mucosa of your partner leading to the transmission of infection.
• While withdrawing the penis after you are done, hold the condom at the base of the penis. This prevents slipping of the condom. Carefully remove the condom and throw it in the trash.
• If the condom slips or breaks during sex, contact your health-care provider to discuss emergency contraception. Additionally, you and your partner must get tested for STIs including HIV.

Health News

Internal or female condoms

If you are using an internal/female condom:

• Ensure that the condom has not crossed its expiration/expiry date.
• Carefully remove the condom from its package.
• You may use any type of lubricant with an internal condom. Using lubricant is advised because it keeps the internal condom at its place and prevents breakage.
• Hold the condom at its closed end, squeeze the sides of the inner ring together and insert it into the vagina or anus.
• Using your finger, push the inner ring upward so that it rests against the cervix (neck of the uterus) in the vagina or as far into the anus as it can go.
• Do not twist the condom and ensure that its thin, outer ring remains outside the vagina or anus.
• After ensuring that the condom is inserted properly, guide your partner’s penis into the condom opening.
• After you are done, gently twist the outer ring and pull the condom out.
• Throw the condom into the trash after a single use.
• If you feel the penis has slipped between the condom and vaginal/anal walls or if the outer ring is pushed into the vagina/anus, stop intercourse.
• If the condom slips or breaks during sex, contact your health-care provider to discuss emergency contraception. Additionally, you and your partner must get tested for STIs including HIV.

If you have been exposed to HIV

The most definitive way of preventing HIV is complete abstinence from vaginal and anal sex. This is, however, not a practical approach because most people will have sex sometimes in their lives. Thus, using condoms is the most effective way for preventing the spread of HIV.

If you think you or your partner have been exposed, get tested for HIV. Take proper treatment if you are tested positive for HIV because it helps keep you healthy and reduces the transmission risk to your partner as well. If you are at a high risk of HIV, discuss pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP) with your doctor.

SLIDESHOW

Medically Reviewed on 4/11/2022

References

SOURCES:

Center for Young Women’s Health: "My pregnancy test was negative and I used protection, but my period is 9 days late. Should I be concerned?"

Centers for Disease Control and Prevention: "Contraception."

Cleveland Clinic: "Condoms."

Johns Hopkins Medicine: "Guy's Guide to Safe Sex."

NHS: "Condoms."

TeensHealth by Nemours: "Are Condoms 100% Effective?" "What if the Condom Breaks?" ?

Why condoms are not fully effective?

Why do condoms not work 100%?

Are condoms 100 effective in preventing pregnancy?

Is it possible to get pregnant while using condoms?