Astadhyayi is a a part of Vyakaranam a Vedic component so women should never read them at any time. These days women who are Sanskrit students read Samanya Shastra. The wives of saints would have read them on in the days gone by and may not have done so during menstrual time. But it is not wrong to study them for exams and similarly for Amarakosha shloka and Sahityam.