In vivo evaluation of an effervescent intravaginal contraceptive insert by simulated coital activity

Sixteen women ages 20 to 41 participated in a project to evaluate the in vivo intravaginal spermicidal effectiveness of nonoxynol-9 foaming suppositories. Testing of each subject was done at 18 different time intervals ranging from 5 seconds to 6 hours following insertion of the vaginal contraceptive. Simulated coitus using a latex dildo was incorporated in the test design to simulate dispersal of the spermicide that occurs during coitus. Semen specimens meeting uniform criteria for sperm count, motility, morphology, and volume were injected intravaginally; three vaginal aspirates were then immediately obtained to evaluate sperm motility microscopically. Maximal spermicidal effectiveness was found between 5 minutes and 1 hour after insertion of the vaginal contraceptive.