Moist environment provides a perfect breeding place for bacteria. Under such circumstances, women are vulnerable to inflammation or infection if without proper care during menstrual period. According to the doctors in obstetrics and gynecology, there are many gynecologic out-patients who suffer from gynecologic diseases due to the improper use of sanitary napkin. It is suggested that the sanitary napkin with cotton surface be used, because cotton surface has better penetrability and comfort. Sanitary napkin with aroma or synthetic material should be avoided. Sanitary napkin should be replaced often during menstrual period to prevent bacteria breeding.