flat spring contraceptive diaphragm, a kind of contraceptive diaphragm in which the flexible metal spring that forms the rim is a thin, light, flat band made of stainless steel. The rubber dome is approximately 3.8 cm deep, and the diameter of the rubber-covered rim is between 55 and 100 mm. Seven sizes, in increments of 5 mm, allow the clinician to fit the diaphragm to a particular woman. This kind of diaphragm is prescribed for a woman whose vaginal musculature provides good support, whose uterus is in the normal position and not acutely retroflexed or anteflexed, and whose vagina, neither very long nor very short, has a shallow arch behind the symphysis pubis.
