The simultaneous absorption of genital secretions and blood was assessed in 61 intravaginal tampons from eight young, healthy, nulliparous volunteers during menstruation. The tampons were self-inserted over the first 3 days of menstruation according to the habit of each subject. Wide variations in the amount of blood and fluid absorbed were noted within and between subjects. The mean amount of genital secretion absorbed was 0.31 g/h and that of menstrual blood was 0.76 g/h. The average tampon absorbed 65% blood and 35% genital secretion.