Masters and Johnson (1966) described 3-15 rhythmic contractions of the orgasmic platform in the outer third of the vagina as the physiological basic of female orgasm. Bohlen et al. (1982) in a more recent research registered in some subjects during "long orgasms" up to 34 additional irregular pelvic contractions. In some subjects no contractions occurred during their orgastic experience. Our own findings are based on Czech sexological questionnaires SGZ and SFZ/K, which include questions asking about subjective experience of vaginal contractions or pulsation during orgasm. In a sample of 200 women treated for neurotic disorders, about 60% reported such contractions or pulsations. In a sample of 100 female health professionals and counselors, contractions were reported in 80%. Contractions seem to frequently accompany subjective experience of female orgasm, but are not its necessary condition. Some women experience their orgasm regularly without contractions and some report having contractions during orgasm only occasionally.