Is withdrawal an effective form of birth control?

What it is: Your partner pulls out during intercourse before ejaculation.
How it works: Technically, it doesn’t. Your partner’s timing may be impeccable, but that doesn’t protect you from pre-ejaculate, which contains sperm.
Effectiveness: About 30% (but see above).
Convenience: Convenient in the heat of the moment; could be inconvenient nine months later.
Best for: Women who are comfortable with the fact they could get pregnant.
Side effects: Pregnancy.
Price tag: Initially, cost-free.
Good to know: If using withdrawal, you should take folic acid because there is a good chance you will get pregnant.

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