Whatever doubt may exist as to the most frequent state of the sexual emotions during the period of menstruation, there can be no doubt whatever that immediately before and immediately after, very commonly at both times,--this varying slightly in different women,--there is usually a marked heightening of actual desire. It is at this period (and sometimes during the menstrual flow) that masturbation may take place in women who at other times have no strong auto-erotic impulse. The only women who do not show this heightening of sexual emotion seem to be those in whom sexual feelings have not yet been definitely called into consciousness, or the small minority, usually suffering from some disorder of sexual or general health, in whom there is a high degree of sexual anæsthesia.[116] The majority of authorities admit a heightening of sexual emotion before or after the menstrual crisis. See e.g., Krafft-Ebing, who places it at the post-menstrual period (_Psychopathia Sexualis_, Eng. translation of tenth edition, p. 27). Adler states that sexual feeling is increased before, during and after menstruation (_Die Mangelhafte Geschlechtsempfindung des Weibes_, 1904, p. 88). Kossmann (Senator and Kaminer, _Health and Disease in Relation to Marriage_, I, 249), advises intercourse just after menstruation, or even during the latter days of the flow, as the period when it is most needed. Guyot says that the eight days after menstruation are the period of sexual desire in women (_Bréviaire de l'Amour Expérimentale_, p. 144). Harry Campbell investigated the periodicity of sexual desire in healthy women of the working classes, in a series of cases, by inquiries made of their husbands who were patients at a London hospital. People of this class are not always skilful in observation, and the method adopted would permit many facts to pass unrecorded; it is, therefore, noteworthy that only in one-third of the cases had no connection between menstruation and sexual feeling been observed; in the other two-thirds, sexual feeling was increased, either before, after, or during the flow, or at all of these times; the proportion of cases in which sexual feeling was increased before the flow, to those in which it was increased after, was as three to two. (H. Campbell, _Nervous Organization of Men and Women_, p. 203.)