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The question

What does a condom actually protect me against?

The answer

With the increasing rate of sexually transmitted infections in Canada, your question is relevant and timely.

When used properly, condoms are very effective for protection against STIs and to prevent pregnancy.

Although they are highly reliable, they are not 100 per cent foolproof. When condoms fail, incorrect or inconsistent use - not the method itself - is usually to blame. In Canada, condoms are considered medical devices and are regulated by Health Canada to meet specific requirements for safety and effectiveness.

According to the Public Health Agency of Canada, "condoms used consistently and correctly provide protection against getting or spreading STIs--including HIV." Studies have shown that condoms provide an impermeable barrier to chlamydia, gonorrhea, Hepatitis B, HIV, syphilis, herpes simplex virus (HSV) and human papilloma virus (HPV).

Certain STIs, specifically HSV, HPV and syphilis (especially when lesions are present) can be transmitted through skin to skin contact. Condoms may work to provide a barrier to transmission of these infections, they are often harbored in skin that is not covered by the condom and as such, they can still be passed on despite use of a condom.

Condoms are still the best defense against transmission,and the reduction is substantial but not absolute.

While the male condom is the more popular, female condoms should also be considered as birth control. This is a polyurethane sheath that is inserted into the vagina up to 8 hours before intercourse. They allow women the freedom to control their own protection - but they can be uncomfortable, expensive and most importantly, if the fit is not correct, they are not as effective against pregnancy or protecting against STIs.

Condoms are inexpensive (and free in sexual health clinics), widely available and simple to use. The following tips may help increase their safety and efficacy:

1. Store your condoms properly: Keep condoms in a cool, dry place. Heat, light, and friction can shorten their shelf-life and decrease their strength, causing them to break down and be less reliable.

2. Choose the right condom for you: Get the right fit as condoms that are too large can slip off and those that are too small can break easily. If you have a latex allergy, non-latex condoms are available in lambskin and polyurethane forms. Lambskin condoms can be more porous and while effective against pregnancy, they are not as effective to protect against STIs.

3. Use proper lubrication: For latex condoms, use only water based lubricants as oil based lubricants can weaken latex material. Polyurethane condoms can be used with both water and oil based lubricants.

4. Avoid novelty condoms: While they may come in fun flavors and texture, these condoms have not been tested for safety or effectiveness so read the package to ensure that they have been approved to protect against infection and pregnancy.

5. Use condoms for oral and anal sex: Dental dams and condoms can be used to protect during oral sex.

6. Use it throughout each sexual encounter: Remember to put a condom on from the beginning to the end, as STIs and pregnancy can occur before ejaculation. If you are having sex more than once in a short time frame, do not reuse the same condom.

7. Avoid the spermicide Nonoxynol 9: While helpful for preventing pregnancy, nonoxynol-9 can actually increase the risk of transmission of STIs by irritating vaginal, rectal and penile tissue.

8. Put the condom on properly: While it may seem straightforward, if you aren't sure how to put a condom on, a helpful site with educational videos and information can be found here

Condoms are the only form of birth control that also protect against STIs, so if you are on the pill or have an IUD, condoms are still important to use.

STIs often do not cause symptoms, so you or your partner may not be aware that you are carrying one. The best and easiest protection we have, apart from abstinence, is consistent and proper condom use and to get tested regularly.

Send family doctor Sheila Wijayasinghe your questions at She will answer select questions, which could appear in The Globe and Mail and/or on The Globe and Mail web site. Your name will not be published if your question is chosen.

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