Effectiveness depends on the user: Risk of pregnancy is greatest when the diaphragm with spermicidDiaphragmse is not used with every act of sex.

  • As commonly used, about 17 pregnancies per 100 women using the diaphragm with spermicide over the first year. This means that 83 of every 100 women using the diaphragm will not become pregnant.
  • When used correctly with every act of sex, about 16 pregnancies per 100 women using the diaphragm with spermicide over the first year.

Return of fertility after use of the diaphragm is stopped: No delay

Protection against STIs: May provide some protection against certain STIs but should not be relied on for STI prevention (see Question 8).