The World Federation One Stop Fiqh

Ruling 483

4. A woman with a disordered habit (muḍṭaribah) 

A muḍṭaribah is a woman who experiences bleeding on two consecutive months but there is a difference in the time and duration of her bleeding. If a muḍṭaribah experiences bleeding for more than ten days and all the blood is the same – i.e. all of it either has the attributes of ḥayḍ or the attributes of istiḥāḍah – then based on obligatory precaution, the rules that apply to her are the same as those that apply to a woman with a habit of time who experiences bleeding at a time other than that of her habit, and who cannot distinguish ḥayḍ from istiḥāḍah by the attributes of the bleeding and so must consider the habit of some of her close relatives to be her habit of ḥayḍ. In case this is not possible, she must choose a number of days between three and ten and consider that to be her ḥayḍ, as per the explanation mentioned in Rulings 479 and 481.