Shake the foam can hard, for about 20 shakes. Then, put the product in an applicator, and empty it into the vagina. The product must reach the cervix to be effective. Foams provide immediate protection, and continue to provide protection for an hour after the foam was inserted. If you have sex again, apply another dose.
Most applicators are reusable.
Wash the applicator with soap and warm water after every use. Yes, you should use spermicides during every act of sex, whether or not you are having your period. In fact, they can help protect against cancer of the cervix. Research indicates that if you use spermicides when you are pregnant, spermicides do not cause birth defects in your baby. Most spermicides can be purchased at drug stores and supermarkets.