What you can expect

To use spermicide:

• Choose a type of spermicide. Foams, gels and creams begin working immediately, while suppositories, films and tablets need to be inserted 10 to 30 minutes before sex to dissolve. If more than one hour passes between the application of spermicide and sex, reapply spermicide.

• Apply spermicide. Find a comfortable position, such as lying down. Using an applicator or your fingers, insert spermicide into your vagina on or near your cervix.

  If you use an applicator, fill the applicator with the recommended amount of cream, gel or foam and insert it into your vagina as far as it will go. Push the plunger on the applicator to release the spermicide near your cervix.

  To insert spermicide by hand, wash and dry your hands and place the suppository, film or tablet on your fingers. Slide your fingers along the back wall of your vagina as far as you can so that the spermicide covers or rests on or near your cervix.

  If you're using spermicide with a diaphragm or cervical cap, follow the instructions that come with the device. If you have sex more than once, apply fresh spermicide before each sexual encounter.

• Be cautious after sex. For maximum effectiveness, make sure the spermicide remains in your vagina for at least six hours after sex. After six hours, there's no need to clean any remaining spermicide from your vagina. Douching isn't recommended — but if you choose to douche after sex, wait at least six hours.

Similar to spermicide, you apply the vaginal pH regulator gel (Phexxi) directly to your vagina. The combination of lactic acid, citric acid and potassium bitartrate in the gel immobilizes sperm so that they can't fertilize an egg. You need to apply the gel within an hour before having sex and reapply the gel each time you have sex.

Talk with your health care provider if you develop persistent vaginal irritation or recurring urinary tract infections after using spermicide or a vaginal pH regulator gel.