Physical contraceptives—spermicides

General information

Spermicides are produced in a variety of formulations, including gels, foams, creams, suppositories, pessaries, capsules, foaming tablets, and melting films. Spermicides are also used in conjunction with other methods, such as diaphragms, condoms, and sponges, but also with intrauterine contraceptive devices and methods based on fertility awareness [ ].

Contraceptive sponges are controversial: do they act by delivering spermicides or as barriers? However, it has been shown conclusively that the newest forms of sponges, which provide not one but a combination of three active spermicides, act much more like spermicides than as simple vaginal barriers.

Spermicides are relatively inexpensive and widely available over the counter in most countries. All currently used formulations contain the non-ionic detergent nonoxynol-9, usually in a dose of 70–230 mg, but the newest formulations may contain octoxynol or benzalkonium chloride [ ]. All chemical agents used in spermicides disrupt the sperm cell membrane and finally rupture the cell.

Spermicides, especially in certain communities, have important advantages over the more modern methods of contraception: they are immediately reversible, are available over the counter without prescription, can be used by breastfeeding women, and are under direct female control.

However, spermicides also have adverse effects. They can cause local irritation in the woman or her partner, especially if they are used several times a day and can very rarely cause local allergic reactions in the woman or her partner.