Contraception - chemical methods

It is possible to use sperm-killing (spermicidal) chemicals as an aid to contraception. One advantage of these products is that you can buy them from any pharmacy without prescription. But these agents really SHOULDN'T be employed on their own, because they're not effective enough. If you use them by themselves, there's a high chance that sperm will get through sometimes - and cause pregnancy.

So, all family planning experts agree that chemical contraception should ONLY be used in combination with a 'barrier method' - such as a condom or a cap. The chemicals make these barrier methods more effective. In other words, fewer pregnancies will occur if you use a condom or cap with a spermicidal chemical. From time to time, manufacturers may suggest that these agents are so good that they can be used on their own! Don't pay any attention to these claims.

There is only one situation in which you might want to use a chemical contraceptive on its own: if you both feel that it wouldn't matter if a pregnancy occurred.

How do chemical contraceptives work?

They work by killing sperm inside the vagina. They do this because they contain a spermicide - that is, an agent which attacks sperm. The commonest spermicide used in these products is called nonoxinol-9.

How do you use them?

You put them into your vagina before intercourse. In the case of solid preparations (see below), you must give them time to dissolve before you start having sex. Follow the instructions on the leaflet in the package.

What types of chemical contraceptives are there?

There are various types and which one you choose is up to you. Generally people make their choice on the basis of what appeals to them aesthetically. For instance, one couple may prefer the feel, appearance and taste of foam, while others prefer the simplicity of a vaginal tablet.

The main types are as follows.

Foams

These are in aerosol form and you insert them into the vagina with a special syringe, immediately before sex.

Vaginal tablets

These are also widely known as pessaries. In some books about sex, you may find them referred to as 'suppositories'. This term has now been dropped - because most people understand the word 'suppository' to mean something put into the rectum.

Gels, jellies and creams

These are mainly intended for spreading onto contraceptive caps before insertion.

Squares of contraceptive film are still marketed in some countries, though they have fallen out of favour in the UK . At one time, manufacturers suggested that the film should be put on the tip of the penis before the start of intercourse. This is risky, and we do not recommend it.

Those containing spermicide were popular in the 1990s but have now dropped out of fashion in Western countries, due to a high pregnancy rate.

Can chemicals harm you?

Various fragrances, colourings and other components are contained in spermicidal products. Not surprisingly, both men and women can become allergic to these ingredients. Symptoms of allergy include soreness, swelling, redness and itching. If allergy occurs, take medical advice and switch to another product (or method).

At present, there is no information as to whether spermicidal products could harm a baby, if pregnancy occurred. (Please note that in some countries, pharmacists may still be selling old-fashioned spermicidal products which can attack rubber. These products, which are mainly oil-based, could make holes in rubber condoms or caps.)

Will spermicidal chemicals protect you against disease?

No. There has been some publicity about the fact that nonoxinol-9 has an anti-germ action. Nonetheless, it cannot give you any worthwhile protection against HIV or other sex infections.

Will spermicidal chemicals last all night?

No. In general, spermicides are only effective for about 45 to 60 minutes. If you go on having sex longer than that (or if you have sex twice), you need to insert a top-up of spermicide.

What brands are available?

This varies from country to country. In the UK , the following brands are on sale. None of these is known to harm condoms or caps:

Delfen (foam)

Double Check (pessaries)

Durex Duragel (gel)

Gynol II (jelly)

Ortho-Creme (cream)

Orthoform (pessaries).

For further help with your contraception, please see our other articles about different contraceptive methods on the site.