On the Secrets of Women

When there is a thick humor humor: in medieval medicine, one of the four vital bodily fluids (blood, phlegm, black bile, and yellow bile) that determined health and temperament in the animal body that is harmful to it, nature diverts it to the external parts of the body, causing scabs on the hands and feet. This is done so that the moisture does not consume the principal organs—namely, the heart, the liver, and others.

Fourth, someone might wonder where the menstrual fluid comes from in a woman during intercourse with a man. It was stated above that when a woman conceives, the menses are retained; therefore, if they are being held back, it is surprising that they should flow during the act of intercourse. To this, it must be said that when a woman conceives, the menses are retained for a specific "final cause" original: "causam finalem"; in Aristotelian philosophy, the ultimate purpose or "why" behind a natural process: so that the fetus growing in the woman’s womb can be nourished by that retained fluid.

However, when a woman engages in intercourse with a man, she experiences great pleasure because the nerves and veins within the vulva original: "vulva"; used here by the author to refer to the female reproductive tract as a whole are stimulated and moved by the presence of the male organ. Thus, through this dilation, the vulva emits fluid. This is natural in the context of intercourse, as the act itself is natural, yet it is, in a sense, "forced" original: "violentus"; in a medieval scientific context, this refers to a movement triggered by an external force rather than the body's internal clock compared to the regular, natural cycle of menstruation.

Furthermore, from the nourishment consumed every day, matter is created that is naturally suited for expulsion during intercourse. This solves the doubt of why pregnant women often have a great appetite for intercourse. This desire exists because of an abundance of "superfluous matter" derived from food. Because the usual menses are being retained for the fetus, yet new matter is still generated daily, the woman feels a strong desire for intercourse; the abundance of this matter causes her vulva to grow warm, and thus she seeks physical union.