All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
Yes, the waiting period of a woman who is still in the age of menstruation is three menstrual periods according to the preponderant view of the scholars .
Allah Says in this regard (what means): {And divorced women shall wait for three menstrual periods (before getting married again.} [Quran 2:228]
The waiting period “Iddah” of a divorced woman [or a woman whose husband has just died] starts from the first day the woman gets divorced [or the day of the death of her husband].
Allah knows best.