Key words: douches, flow measurements, tech support, research
Vaginal douches are over-the-counter products typically used by women for cleansing and for the relief of vaginal itching and irritation. Douches used for cleansing are considered cosmetics while medicated douches are regulated as drugs. Several device types are available, including a pre-filled disposable bottle, a refillable hanging bag, and a refillable expandable bag. Many past studies reported in the literature have suggested a possible association between vaginal douching and adverse conditions, such as pelvic inflammatory disease (PID), ectopic pregnancy, infertility, and cervical cancer.
One recent clinical study examined the effects of different douche types on the rate of ectopic pregnancy and revealed a higher incidence of ectopic pregnancy when using an expandable bag douche. That study led to a meeting of Nonprescription Drugs Advisory Committee, held April 15, 1997, to discuss adverse issues related to the effects of vaginal douching. Prior to that meeting, OST scientists conducted fluid flow experiments to determine whether fluid dynamic effects contributed to adverse events. The data and results of the experiments were presented at the Advisory Committee meeting.
Douches were studied using the highest pressures and flow rates obtainable with the various product types. Orifice pressures varied widely from 20 to 120 mmHg for the disposable bottles versus approximately 40 to 80 mmHg for the bag types. These pressure differences resulted in velocity differences of less than a factor of two.
Thus, it was concluded that differences in the fluid velocities of the emitted water jets produced by the various douche designs were not likely to be important, because the jet impingement on the vaginal tissue was similar for all products. However, the bag-type products delivered significantly greater overall volumes, 1600 to 1800 ml versus 100 to 150 ml for he disposable bottles, which means the bottles produced longer exposure times (8x greater) than the disposable bottles. This finding may be a contributing factor to the adverse effects seen with the bag-type douche devices.
The Panel concluded that changes in the labeling of vaginal douches, including warnings about the risk of PID associated with douching, were warranted. In addition, educational materials should be made available to practicing clinicians.