Is it permissible to say that it is unlawful for a woman who has reached menopause to become pregnant, taking into consideration the story of the pregnancy of Zachariah's wife with John (peace be upon them both) when she was old, and is this specific to prophets, or can it happen to ordinary women after the age of forty-five?

There is no religious impediment to stating that a woman has reached menopause if her menstrual cycle has ceased, indicating that she has passed the stage of pregnancy and childbirth. This is supported by the Almighty's saying: "And those of your women who have despaired of menstruation." As for what happened to Zakariya and Ibrahim (peace be upon them) and their wives, it is among the signs of Allah's special power concerning them, and it does not apply to people in general.