What is the ruling on continuous bleeding and discharge after forty days (postpartum) and the insertion of an IUD, and is it permissible to fast with it, and what is the ruling on fasting the days during which bleeding occurred, especially the first day when the fast was broken?

The majority of scholars hold that the maximum period for post-natal bleeding (nifas) is forty days, and anything beyond that is considered irregular bleeding (istihadah), unless it coincides with the woman's regular menstrual period. Therefore, if the nifas has exceeded forty days, then any spotting or bloody or brownish discharge thereafter is not considered menstruation for two reasons: firstly, because menstruation is flowing blood, not just spotting; and secondly, because discharges like yellowish or brownish discharge (sufra and kudrah) after purification are not considered menstruation. Hence, one must fast and pray, and make up for any missed prayers during these days.