Niddah 5: Regular Menstrual Cycles

The rabbis clarify their ruling.  It is only a woman who has a veset kavu'a, regular menstrual cycle, who becomes a niddah and thus imparts ritual impurity from the moment that she examines herself and finds blood.  

The bulk of today's daf focuses on women who check for blood both before and after sexual intercourse.  It is noted that men should examine themselves before and after intercourse as well.  There is some concern about women's capacity to check herself properly (inside all folds of skin) when she is excited for intercourse.  The rabbis argue about whether this was required only during the time of the Temple, when people were deemed ritually impure for the purpose of touching consecrated objects.  The Rambam is one of those who argues that these laws applied after the laws of ritual purity no longer were used.  Instead, they are only a requirement for women who do not have a veset kavu'a.

Steinsaltz teaches that the halacha is that a woman who has a regular cycle should not examine herself for menstrual blood after relations.  Regarding a woman who does not have a regular cycle, both she and her husband should check themselves after the first three times that they have intercourse.  If no blood is seen at that time, it is decided that the act of intercourse does not lead to menstruation and there is no need for further examination.

The rabbis' limited understandings regarding menstrual blood and other types of blood coming from the vagina is puzzling.  The rabbis seem to have a limited understanding of women's anatomy, and yet they speak with great confidence and authority.  Reading this as a woman is challenging - but not (yet) disturbing.