Musannaf Ibn Abi Shaybah

Hasan (may Allah have mercy on him) said that if a man is married to a woman who does not menstruate due to immaturity or old age, then the man may divorce her whenever he wishes.

Hazrat Umar bin Abdul Aziz (may Allah have mercy on him) liked that a woman who does not menstruate should be divorced at the sighting of the new moon.

Hazrat Sha’bi (may Allah have mercy on him) says that such a woman should be divorced according to the lunar calendar.

Ibrahim (may Allah have mercy on him) says that if a man is married to a woman who does not menstruate due to immaturity or old age, and the man wishes to divorce her, he should divorce her at the beginning of the lunar month, and then not divorce her again until the waiting period is completed.