One of the author’s patients, a young woman of twenty-two, mother of one child, was sexually so excited during menstruation that her husband asked for a remedy to appease his wife’s excitement quæ menstruata poscebat concubitus frequentes. Initus during this period had an unaesthetic effect upon the highly cultured husband. The increase of the sexual impulse usually begins a few days before menstruation sets in and lasts a few days after its cessation. Yet, although there is an extreme enhancement of concupiscence during the catamenial period, the aversion to initus during this time by men and women is, generally, real. It is due not to lack of sexual desire, but to inhibitory action of powerful extraneous causes that are largely psychological in character. There is the aesthetic repugnance to union, when such a condition obtains, then there are the inhibitory effects derived from the educational suggestions, inculcated in females as well as in males from the time of puberty.[CV] Common experience has also shown since time immemorial that concarnatio during this period is fraught with many dangers. Prominent among them is the possibility of rupturing the impaired vessels and of causing haematometra. The marital relations should, therefore, be suspended during the menstrual period. _Pregnancy._—In the higher animals the female does not admit the male after impregnation has taken place. In man it is different. The act is here a relation of love, mutually demanded and enjoyed by both sexes. It serves other purposes besides that of procreation. Hence initus does take place during pregnancy. Although the woman’s sexual appetence is somewhat lessened during that time, yet the libidinous cycles generally continue far into the later months of pregnancy. In some cases an increased sexual desire has been observed. One of the author’s patients, a lady of twenty-two years of age, was sexually so excited during her first pregnancy that ter quaterque quot noctibus congressus petebat, and but for the refusal of her husband, she would have indulged in more frequent gratification. Another woman was known to the author who became sexually so excited during her pregnancy that for the gratification of her increased sexual desires meretricium faciebat for the entire period. There is, therefore, no natural cessation of the sexual desires even in a woman. Yet at that time, concarnatio should very rarely be indulged in. If it is practised too frequently it leads to considerable disturbances of circulation, and the result may be a miscarriage. Another danger lurking from initus at the time of pregnancy, is the infection of the woman. If it is admitted that the finger of the obstetrician may be the agent of infection, we can hardly deny that the penis may exert the same influence. The husband should hence abstain from sexual relations with his wife during the latter days of gestation.