spermicides

Spermicides are substances designed to prevent pregnancy by impairing sperm function. They are used alone or in combination with barrier methods such as condoms or diaphragms. Spermicides are available in several forms, including gels, foams, creams, films, and dissolvable suppositories, and less commonly, vaginal sponges or rings that release spermicide.

Most spermicides in common use contain nonoxynol-9 as the active ingredient; older products used octoxynol-9. Nonoxynol-9 acts as a surfactant that disrupts sperm membranes, reducing motility and viability. Spermicide alone provides relatively modest protection against pregnancy; effectiveness improves when used with a barrier method. It does not protect against sexually transmitted infections, and frequent use of nonoxynol-9 can irritate vaginal tissue and may slightly increase the risk of acquiring HIV or other infections.

Use involves inserting the product into the vagina before intercourse, with timing depending on product type. Some forms require reapplication for multiple acts or after a certain period. Spermicides may cause vaginal irritation or allergic reactions in some people and can exacerbate irritation with frequent use, which in turn can raise infection risk.

Pregnancy rates with spermicides alone are higher than many other contraceptive methods, and user adherence strongly affects effectiveness. For those seeking reliable contraception, spermicides are often used as a supplement to barriers or may be considered alongside hormonal methods or long-acting reversible methods to improve overall protection.