Barrier Methods of Birth Control
One disadvantage of the diaphragm is the fact that it must remain inside the woman for 6 to 8 hours for the spermacide to effectively kill all of the sperm. This may change as faster acting spermacides are developed.
Another factor inhibiting the popularity of diaphragms is the lack of over the counter availability in the United States. This is to ensure that the device is the right size for the woman. Most places in Europe offer diaphragms over the counter.
After the diaphragm is removed it may be washed and stored for reuse.
Cervical Cap
Cervical caps are smaller than diaphragms but work in similar manner. Cervical caps also rest on the on the cervix (hence the name) but they remain in place by suction.
Cervical caps should also be used with a spermacide.