Answer: Niddah is a spiritual state of impurity and is meant to get rid of all the shells, Klipot, (impure desires) that are left after the correction. They are called Gevurot (limiting forces, Dinim) or Lev HaEven (heart of stone), and they are disconnected from the desire to receive, called woman, and thus she is purified.
Here lies the whole system of the universe. After all, in the same way as our body develops, our soul evolves When I speak about concepts such as the desire to receive, the desire to bestow, the three lines, ten Sefirot, etc., they are depicted in my mind and not the physical states of our male and female bodies.
Question: Do we refer to egoistic thoughts only when we speak about a woman’s impurity, to receiving, to living for my own sake?
Answer: No, a woman who gives birth doesn’t do it for her own sake because otherwise she wouldn’t give birth. Therefore, a state of purity emerges when she is ready to join bestowal. After her monthly cycle ends, it is necessary to wait seven days during which Malchut ascends to Bina, and then she is ready to be fertilized.
From the Kabbalah Lesson in Russian 4/24/16