On quantitative cultures using media selective for staphylococci, 15 of 145 healthy women (10.3%) had Staphylococcus aureus isolated from the vagina; numbers of staphylococci ranged from 3 x 10(1) to 7.3 x 10(7) per swab. Nine of 15 women who were S. aureus vaginal carriers were also nasal carriers, but only 30 of 130 of women without vaginal S. aureus also had coagulase-positive staphylococci in the nose (p = 0.002). Among women with S. aureus at both sites, the numbers of vaginal and nasal staphylococci isolated were not correlated. No association was found between the presence of vaginal staphylococcal colonization and the use of tampons compared to napkins. Cultures taken during menstruation from which S. aureus were isolated contained significantly higher numbers of coagulase-positive staphylococci (mean log +/- SE of 4.0 +/- 0.3) than positive cultures after menstruation (3.3 +/- 0.2) (p less than 0.02).