Benefits and Drawbacks

Effectiveness 

Spermicides are not as effective as many other birth control methods, such as birth control pills or intrauterine devices (IUDs). How well spermicides prevent pregnancy when used alone is not certain. However, the FDA cites failure rates for typical users from 20-50%. Spermicides are most effective when used with a barrier method, such as a condom.   
 
Advantages
 
Spermicides are available over the counter. They do not usually affect other systems in the body. Women can use spermicides without involving their partners in the decision if they wish. When used with a condom, they are very effective. Spermicides may provide additional lubrication during intercourse.
 
Disadvantages
 
Some spermicides may be inconvenient, as they often require a waiting period of several minutes before they are effective. A woman must plan ahead and keep a supply available. The spermicide must be reapplied before each act of intercourse. Some women report messiness and leakage. Spermicides may irritate the vagina or penis. Switching brands may alleviate this problem. Serious medical risks are rare and include irritation, allergic reactions, and urinary tract infections.
 
Spermicides were once thought to provide minimal protection against STDs such as chlamydia and gonorrhea. However, this is no longer believed to be true. In fact, irritation of the vaginal surface may increase susceptibility to some STDs, especially HIV, when the spermicide is used several times a day. Women who want to reduce the risk of STDs should always use a latex condom. 
 
Women who should not use spermicides
 
Any woman with a history of toxic shock syndrome should not insert anything in the vagina that remains there for any length of time, including tampons, diaphragms, or sponges.