Is it permissible for the husband to demand that his wife waive her deferred dower (mu’akkar as-sadaq) or the entire dower (mahr), when she requests a divorce due to his infertility, or is he obligated to pay the dower?

A wife is permitted to request a divorce if it is proven that her husband is infertile. The husband is permitted to refuse to divorce her until she waives her deferred dowry, or a portion of it, or other matters agreed upon by both parties. However, if he divorces her before demanding that she waive her rights, he then becomes obligated to fulfill those rights, and he cannot subsequently retract the divorce until she waives something for him.