Duration of menstruation

Menstrual length was analysed in 2,342 women attending the Shepherd Foundation. Prolonged menses were more common in Australian and New Zealand born, in women with irregular, short or long menstrual cycles, menstrual pain, high parity, and an intrauterine device. In contrast to women with premenstrual tension and menstrual pain, psychological factors, smoking and drinking were not more common in women with increased menstrual length. It is concluded that somatic factors alone control menstrual length, and results in the present study support the hypotheses that both the hypothalamic-pituitary system and prostaglandins may be involved in this control. Evidence was found that the use of the contraceptive pill reduces the incidence of premenstrual tension when menstrual length is also reduced.