Someone else would cook during a woman’s menstrual period and offer it to Perumal. Are women allowed to partake prasadam offered to Perumal during that time? Or should food be cooked separately for them?

During a woman’s menstrual period, the food that was offered to Perumal should be served to elders of the household first and later that food can be served to her.
Notes:
The leftover food from the portion after being served to her, should not be used again. So, it is better to cook for her separately.