Reference: Sharh ‘Umdatil-Fiqh – Tape No.7, Question No.2
Question: Is it permissible for the menstruating woman to enter the mas’aa (area where the sa’ee is done) and remain there?
Response: Yes, [because] the mas’aa is not a [part of the] masjid, rather it is only a place for the sacred rites of the sa’ee. So, it is permissible to perform the sa’ee [even] while she is menstruating, because being in the state of purity is not a precondition for performing the sa’ee, [so] it is permissible for her to sit there because it is not considered part of the masjid. It is a separate place for the sacred rites [of the sa’ee], even if today it has been made part of the masjid, yet it’s original ruling remains in place.