All about spermicide

What it is: A sperm-killing chemical in a cream, gel, foam or suppository.
How it works: Destroys sperm on contact.
Effectiveness: Used alone, it’s between 71 to 82%.
Convenience: A bit of a mood killer — it needs to be inserted right before sex (it’s effective for about an hour) and can be messy.
Best for: Women who are using a barrier method (such as a diaphragm) who want some extra peace of mind.
Side effects: May irritate both partners’ genitals.
Price tag: About $15 a tube.
Good to know: Spermicide offers protection from bacterial infections and pelvic inflammatory disease, and can be used as emergency backup (for instance, in case of a condom mishap, spermicide can kill any escaped sperm on contact).

Our experts:
Dara Maker, family physician at Women’s College Hospital in Toronto
Roey Malleson, clinical associate professor of family practice at University of British Columbia
Ronald Weiss, assistant professor of medicine at University of Ottawa