This ignorance has been fostered by the fact that women, often disguise even to themselves the real state of their feelings. One lady remarks that while she would be very ready for coitus during menstruation, the thought that it is impossible during that time makes her put the idea of it out of her mind. I have reason to think that this statement may be taken to represent the real feelings of very many women. The aversion to coitus is real, but it is often due, not to failure of sexual desire, but to the inhibitory action of powerful extraneous causes. The absence of active sexual desire in women during the height of the flow may thus be regarded as, in part, a physiological fact, following from the correspondence of the actual menstrual flow to the period of _pro-oestrum_, and in part, a psychological fact due to the æsthetic repugnance to union when in such a condition, and to the unquestioned acceptance of the general belief that at such a period intercourse is out of the question. Some of the strongest factors of modesty, especially the fear of causing disgust and the sense of the demands of ceremonial ritual, would thus help to hold in check the sexual emotions during this period, and when, under the influence of insanity, these motives are in abeyance, the coincidence of sexual desire with the menstrual flow often becomes more obvious.[112] It must be added that, especially among the lower social classes, the primitive belief of the savage that coitus during menstruation is bad for the man still persists. Ploss and Bartels mention that among the peasants in some parts of Germany, where it is believed that impregnation is impossible during menstruation, coitus at that time would be frequent were it not thought dangerous for the man.[113] It has also been a common belief both in ancient and modern times that coitus during menstruation engenders monsters.[114] Notwithstanding all the obstacles that are thus placed in the way of coitus during menstruation, there is nevertheless good reason to believe that the first coitus very frequently takes place at this point of least psychic resistance. When still a student I was struck by the occurrence of cases in which seduction took place during the menstrual flow, though at that time they seemed to me inexplicable, except as evidencing brutality on the part of the seducer. Négrier,[115] in the lying-in wards of the Hôtel-Dieu at Angers, constantly found that the women from the country who came there pregnant as the result of a single coitus had been impregnated at or near the menstrual epoch, more especially when the period coincided with a feast-day, as St. John's Day or Christmas.