Is it permissible for a woman to become lawful for her husband again after he has divorced her three separate times, knowing that the first divorce occurred while she was pregnant and he took her back after a day, the second was during a period of purity in which he had intercourse with her and he took her back, and the third occurred while she was menstruating, without her husband's knowledge of her menstruation?

The first divorce pronounced by the husband during pregnancy is effective by agreement of the scholars. As for the last two divorces, they are effective according to the majority of scholars, which is the preponderant opinion. It should be known that the husband does not sin if he pronounces divorce without knowing about the onset of menstruation. Based on this, the divorce has become threefold, and the husband is not permitted to take back his divorced wife, nor does she become lawful for him until she marries another husband in a valid marriage and he then divorces her after consummating the marriage. She has also become a stranger to him, so it is not permissible for him to be in seclusion with her, nor is it lawful for him to see her except with her full hijab (definition).