[8][9] Before inserting or removing a diaphragm, one's hands should be washed[10] to avoid introducing harmful bacteria into the vaginal canal.

[11] The diaphragm must be inserted sometime before sexual intercourse, and remain in the vagina for 6 to 8 hours after a man's last ejaculation.

Lubricants or vaginal medications that contain oil will cause the latex to rapidly degrade and greatly increases the chances of the diaphragm breaking or tearing.

Contraceptive Technology reports that the method failure rate of the diaphragm with spermicide is 6% per year.

[18] The diaphragm does not interfere with a woman's menstrual cycle, therefore, no reversal or waiting time is necessary if contraception is no longer wanted or needed.

Many women, especially those who have sex less frequently, prefer barrier contraception such as the diaphragm over methods that require some action every day.

[10] Like all cervical barriers, diaphragms may be inserted several hours before use, allowing uninterrupted foreplay and intercourse.

[14] However, research conducted to test whether the diaphragm offers protection from HIV found that women provided with both male condoms and a diaphragm experienced the same rate of HIV infection as women provided with male condoms alone.

[21] Diaphragms are also considered a good candidate as a delivery method for microbicides (preparations that, used vaginally, protect against STIs) that are currently in development.

[10] Toxic shock syndrome (TSS) occurs at a rate of 2.4 cases per 100,000 women using diaphragms, almost exclusively when the device is left in place longer than 24 hours.

[23] For this reason, some advocate use of lactic acid or lemon juice based spermicides, which might have fewer side effects.

The SILCS diaphragm is made of silicone, has an arcing spring, and a finger cup is molded on one end for easy removal.

A diaphragm that is too large will place pressure on the urethra, preventing the bladder from emptying completely and increasing the risk of urinary tract infection.

[12] The traditional clinical guideline is that a decrease in weight may cause a woman to need a larger size, although the strength of this relationship has been questioned.

[10] Full-term vaginal delivery especially will tend to increase the size diaphragm a woman needs, although the changes to the pelvic floor during pregnancy mean even women who experience second-trimester miscarriage, or deliver by C-section, should be refitted.

This means that during intercourse, the diaphragm will not fit snugly against the pubic bone because it is carried higher up the vaginal canal by the movement of the cervix.

If the diaphragm is inserted after arousal has begun, extra care must be taken to ensure the device is covering the cervix.

[30][needs update] It is widely taught that additional spermicide must be placed in the vagina if intercourse occurs more than six hours after insertion.

It has been suggested that diaphragms be dispensed as a one-size-fits-all device, providing all women with the most common size (70 mm).

Various cultures have used cervix-shaped devices such as oiled paper cones or lemon halves, or have made sticky mixtures that include honey or cedar resin to be applied to the cervical opening.

An important precursor to the invention of the diaphragm was the rubber vulcanization process, patented by Charles Goodyear in 1844.

In the 1880s, a German gynecologist, Wilhelm P. J. Mensinga, published the first description of a rubber contraceptive device with a spring molded into the rim.

[46][47][48] In the United States, the physician Edward Bliss Foote designed and sold an early form of occlusive pessary under the name "womb veil" starting in the 1860s.

Sanger learned about the diaphragm in the Netherlands and introduced the product to the United States when she returned in 1916.

Sanger and her second husband, Noah Slee, illegally imported large quantities of the devices from Germany and the Netherlands.

The number of women using diaphragms dropped dramatically after the 1960s introduction of the intrauterine device and the combined oral contraceptive pill.

[48] That number has continued to fall, and in 2002 only 0.2% of American women were using a diaphragm as their primary method of contraception.

[51] In 2014 Janssen Pharmaceuticals announced the discontinuation of the Ortho-All Flex Diaphragm, making it very difficult for women in the U.S. to have that option as a birth-control method.

[54] Since then, Kessel has also developed a traditionally circular, multi-sized diaphragm made from the same materials that they released in Germany in 2020 under the name Singa.