Effectiveness rates for the diaphragm range from 84% (typical use) to 94% (perfect use). Correct and consistent use has been found to be an important factor in effectiveness rates. It is estimated that half of diaphragm users who become pregnant were using the method incorrectly (Hatcher et al., 2004). Women who have not had children have been found to have higher effectiveness rates than those women who have given birth.
The diaphragm can be inserted prior to sexual activity, which increases spontaneity. In addition, the spermicidal cream or jelly provides some protection from STIs and pelvic inflammatory disease (PID), and it also reduces the risk of cervical dysplasia and/or cancer (Hatcher et al., 2004). The diaphragm does not affect hormonal levels and is relatively inexpensive. In addition, although it does not require partner involvement, men can be involved in the insertion of the diaphragm if desired.