Is it permissible to take medication to prolong the menstrual period?

Menstrual blood is a natural blood, usually flowing for six to seven days, and not exceeding fifteen days. If it exceeds that, it is blood of istihadah (non-menstrual bleeding), which is an impurity that prevents a woman from prayer, reciting the Quran, and marital intimacy. Women naturally desire to be rid of it, not to induce it. Some doctors have stated that inducing it with medications is harmful to a woman's health. If harm is proven, then it is not permissible, based on the Almighty's saying: "And do not kill yourselves. Indeed, Allah is to you ever Merciful," and the Prophet's (peace be upon him) saying: "There should be neither harming nor reciprocating harm." However, if there is no harm, then it is not forbidden.