Ruling 477

Women who have a habit of time and whose habit has a fixed start date are of two types:

1. A woman who on two consecutive months has her period at a fixed time and whose period stops after a few days but the number of days in each month is not the same. For example, on two consecutive months she experiences bleeding on the first of the month but in the first month the bleeding stops on the seventh, and in the second month the bleeding stops on the eighth. This woman must consider the first of the month to be the first day of her habit of ḥayḍ;
2. A woman who on two consecutive months has her period at a fixed time for three or more days, then her period stops, and then she experiences bleeding again, and all the days on which she experiences bleeding plus the days in between on which her bleeding stops do not exceed ten; but in the second month, this figure is more or less than the first month. For example, in the first month it is eight days and in the second month nine days but in both months she experiences bleeding from the first of the month. Such a woman must also consider the first of the month to be the first day of her habit of ḥayḍ.