A perineal dilator is an inflatable bubble-like device used to prepare women for the experience of childbirth. The device, usually made out of silicone, is inserted into the vagina and inflated, and then pushed out. Use of the device allows gradual stretching of the perineum in order to prevent trauma to the perineum during childbirth. It also allows a woman to practice pushing an object out of the vagina. The device can be inflated to varying sizes up to the typical size of a fetus's head.
The use of a perineal dilator was reported in telephone interviews of Israeli women to reduce the rate of episiotomy. These results may be due to any combination of factors, including a shortening of labor due to giving women practice with pushing, stretching of the perineum, and empowering women to participate in the decision of whether or not to have an episiotomy.[1]
One commercially available device, made by the German company Tecsana, is called the "Epi-no birth trainer", in reference to the fact that the device is intended to avoid the use of episiotomy.[2][3]
Where episiotomy is never practiced, the sutured tear rates using midwifery model care were 34% for first births (Albers et al. 2005).
Among 104 consecutive primiparous women who practiced with an Epi-No birth trainer before birth and had normal vaginal births, 10% had sutured perineums. Neither group suffered any third- or fourth-degree tears. The average birthweight was 3,400 g. This 10% rate of sutured perineums is the lowest reported for healthy primiparous women to date (Cohain 2008, p. 167).