Parashas Acharei Mos · Passuk 18:19
Chabad.org — English translation + Rashi
Torah Temima points to Yerushalmi Sanhedrin 7:7.
English: “Do not approach to uncover” — she herself is forbidden both to approach and to uncover.
Woman equally bound
The niddah herself is commanded not to approach or uncover, parallel to the man.