Is a woman's fasting valid if her postpartum bleeding stops in the first third of Ramadan and she sees a lot of white discharge, and is she considered pure in this case?

If a woman in postpartum bleeding (nifas) sees purity before the forty-day mark, she should perform ghusl (ritual bath), pray, and fast. Purity is recognized by one of two signs: the emission of a white discharge (al-qassah al-bayda'), or complete dryness, meaning no trace of blood, yellowish discharge, or brownish discharge remains. So, if the blood stops and no trace of it, nor of yellowish or brownish discharge, remains, this is a sign of her purity, and her fasting is valid. The emission of white water does not harm her; it is either al-qassah or vaginal secretions.