What is the ruling on the blood that comes down as spots or in a brown color after the usual post-menstrual purification, following the insertion of an IUD, and must one stop praying because of it?

If a woman becomes pure from menstruation, by one of the two signs of purity (dryness or white discharge), she must perform ghusl and pray, and it is permissible for her husband to have intercourse with her. If she sees blood after that, she should consider it menses and refrain from what a menstruating woman refrains from, unless the total days of the two blood periods and the period of purity between them exceed fifteen days. As for yellow or brownish discharge after purity, it is not considered menstruation.