Does a divorce issued by the husband under the wife's threat of suicide and self-harm take effect, and what is the ruling on a divorce that occurred while the woman was menstruating, according to the Maliki school of thought?

Divorce does not take effect from a husband who is coerced, based on the hadith: "No divorce in coercion (Ighlaq)." Coercion here refers to that which involves painful fear. The scenario in question—a wife threatening to kill herself if her husband does not divorce her—falls under valid coercion. Therefore, the husband's divorce in this situation does not take effect. It is incumbent upon a Muslim to follow the truth wherever it becomes clear to him.