What is the ruling on a vow of unspecified duration to refrain from praying for death upon oneself, and what is the way to annul this vow?

A wife's prayer for death upon herself is not permissible, and whoever does so has committed a reprehensible act (makruh) or a sin. The husband should not advise her to make vows, as there is a confirmed prohibition against it. If the wife vows that a vow becomes binding upon her every time she prays for death upon herself, this is a vow of obstinacy (nذر لجاج), and the preponderant opinion concerning it is a single expiation for an oath (kaffarat yamin). It is forbidden for her to repeat praying for death upon herself.