Mechanism of Contraception
The spring in the rim of the diaphragm forms a seal against the vaginal walls. The diaphragm covers the cervix, and physically prevents sperm from entering the uterus through the os.
Traditionally, the diaphragm has been used with spermicide, and it is widely believed the spermicide significantly increases the effectiveness of the diaphragm. Insufficient studies have been conducted to determine effectiveness without spermicide.
It is widely taught that additional spermicide must be placed in the vagina if intercourse occurs more than six hours after insertion. However, there has been very little research on how long spermicide remains active within the diaphragm. One study found that spermicidal jelly and creme used in a diaphragm retained its full spermicidal activity for twelve hours after placement of the diaphragm.
It has long been recommended that the diaphragm be left in place for at least six or eight hours after intercourse. No studies have been done to determine the validity of this recommendation, however, and some medical professionals have suggested intervals of four hours or even two hours are sufficient to ensure efficacy. Interestingly, one manufacturer of contraceptive sponges only recommends leaving the sponge in place for two hours after intercourse. However, such use of the diaphragm (removal before 6 hours post-intercourse) has never been formally studied, and cannot be recommended.
It has been suggested that diaphragms be dispensed as a one-size-fits-all device, providing all women with the most common size (70mm). However, only 33% of women fitted for a diaphragm are prescribed a 70mm size, and correct sizing of the diaphragm is widely considered necessary.
Read more about this topic: Diaphragm (contraceptive)
Famous quotes containing the words mechanism of and/or mechanism:
“A mechanism of some kind stands between us and almost every act of our lives.”
—Sarah Patton Boyle, U.S. civil rights activist and author. The Desegregated Heart, part 3, ch. 2 (1962)
“The two elements the traveler first captures in the big city are extrahuman architecture and furious rhythm. Geometry and anguish. At first glance, the rhythm may be confused with gaiety, but when you look more closely at the mechanism of social life and the painful slavery of both men and machines, you see that it is nothing but a kind of typical, empty anguish that makes even crime and gangs forgivable means of escape.”
—Federico García Lorca (1898–1936)