What Is It?

Condoms are a barrier method of contraception. There are male condoms and female condoms. A male condom is a thin sheath (usually made of latex, a type of rubber) that is worn on the penis. A female condom is a polyurethane sheath with a flexible ring at either end. One end is closed and inserted into the vagina; the other end is open and the ring sits outside the opening of the vagina. The male condom, sometimes called a "rubber" or "prophylactic," is far more commonly used.

How Does It Work?

Condoms work by keeping semen (the fluid that contains sperm) from entering the vagina. The male condom is placed on a guy's penis when it becomes erect (and before any sexual contact). It is unrolled all the way to the base of the penis while holding the tip of the condom to leave some extra room at the end. This creates a space for semen after ejaculation and makes it less likely that the condom will break.

After the guy ejaculates, he should hold the condom at the base of the penis as he pulls out of the vagina. He must do this while the penis is still erect to prevent the condom from slipping off when he gets soft. If this happens, sperm could enter the vagina.

Female Condom

The female condom is inserted into the vagina using the closed-end ring. The other ring creates the open end of the condom. The sheath then lines the walls of the vagina, creating a barrier between the sperm and the cervix. The female condom can be inserted up to 8 hours prior to intercourse. It should be removed immediately after sex.

The male and female condoms should not be used at the same time because they can get stuck together and cause one or the other to slip during intercourse, making them ineffective.

Condom Precautions

Once a condom is used, it cannot be reused. A new condom should be used each time you have sex — and it must be used from start to finish every time you have sex to prevent pregnancy and sexually transmitted diseases (STDs). Never use oil-based lubricants such as mineral oil, petroleum jelly, or baby oil with condoms because these substances can break down the rubber. A used condom should be thrown in the garbage, not down the toilet.

And if a condom ever seems dry, sticky, or stiff when it comes out of the package, or if it is past its expiration date, throw it away and use a new one. It's a good idea to have several condoms on hand in case there is a problem with one. It's best to store unused condoms in a cool, dry place.

How Well Does It Work?

Over the course of a year, 15 out of 100 typical couples who rely on male condoms alone to prevent pregnancy will have an accidental pregnancy. The use of the female condom is a little less reliable and 21 out of 100 couples will have an unintended pregnancy.

Of course, these are average figures and the chance of getting pregnant depends on whether you use condoms correctly every time you have sex.

The most common reason that condoms "fail" is that the couple fails to use one at all. Still, it is possible for a condom to break or slip during intercourse. Condoms can also be damaged by things like fingernails and body piercings.

Experts used to think that using spermicide with a condom would decrease the pregnancy rate as well as help fight against STIs. However, more recent information indicates that this is not necessarily true and spermicide does not help make condoms more effective.

In general, how well each type of birth control method works depends on a lot of things. One factor is whether the method chosen is convenient — and whether the person remembers to use it correctly all the time.

Protection Against STIs

Most male condoms are made of latex. Those made of lambskin may offer less protection against some STIs, including HIV/AIDS, so use of latex condoms is recommended. For people who may have an allergic skin reaction to latex, both male and female condoms made of polyurethane are available.

When properly used, latex and polyurethane condoms are effective against most STIs. Condoms do not protect against infections spread from sores on the skin not covered by a condom (such as the base of the penis or scrotum). For those having sex, condoms must always be used to protect against STIs even when using another method of birth control.

Abstinence (not having sex) is the only method that always prevents pregnancy and STIs.

Possible Side Effects

Most men and women have no problems using condoms. Side effects that can occasionally occur include:

• allergy to latex condoms
• irritation of the penis or the vagina from spermicides or lubricants that some condoms are treated with

Who Uses It?

Couples who are responsible enough to stop and put a condom on each time before sex and people who want protection against STIs use condoms. Because condoms are the only method of birth control currently available for men, they allow the guy to take responsibility for birth control and STI protection. Condoms are also a good choice for people who do not have a lot of money to spend on birth control.

How Do You Get It?

Condoms are available without a prescription and are sold in drugstores, supermarkets, and even vending machines (in some stores, they're in the "Family Planning" aisle). Condoms come in different sizes, textures, and colors.

How Much Does It Cost?

Condoms are the least expensive and most available method of birth control — other than abstinence, of course. Male condoms cost about $0.50 to $1 each and are less expensive when they are bought in boxes that contain several condoms.

In addition, many health centers and family planning clinics (such as Planned Parenthood) and some schools distribute them free of charge. Female condoms are a little more expensive and cost about $2 to $4 per condom.

Reviewed by: Larissa Hirsch, MD
Date reviewed: September 2009