Contraceptive sponges and some condoms also contain spermicide.
Spermicides prevent pregnancy by killing sperm before they reach the uterus.
The instructions for using each type of spermicide are different. Make sure that you follow the directions on the package carefully. Call your doctor if you have any questions. Insert the applicator or suppository deep into the vagina like you would a tampon. If you use a suppository, you must wait 15 minutes before having sex.