* Among couples who initiate use of a method (not necessarily for the first time) and who use it perfectly (both consistently and correctly), the author’s best guess of the percentage expected to experience an accidental pregnancy during the first year if they do not stop use for any other reason.

** Among typical couples who initiate use of a method (not necessarily for the first time), the percentage who experience an accidental pregnancy during the first year if they do not stop use for any other reason.

The lowest expected and typical percentages are based on data from populations in which contraception is not used and from women who cease using contraception in order to become pregnant. These represent our best guess of the percent who would conceive among women now relying on reversible methods of contraception if they abandon contraception all together. The lowest reported percent is based on United States women who use no contraception even though they do not wish to become pregnant. This group is selected for low fecundity or low coital frequency and some fraction may use an unreported variant of periodic abstinence.

• Foams and Vaginal suppositories
• Cervical Mucus (ovulation) method supplemented by calendar in the preovulatory and basal body temperature in the postovulatory phases.
• With spermicidal cream or jelly
• Without Spermicides