Hi, Cerazette contains desogestrel, a natural hormone progesterone that is used in the prevention of unwanted pregnancies from unprotected sexual intercourses. It is also used to treat heavy, irregular or painful menstrual cycles. Desogestrel like Cerazette may pass into breast milk. But, the excreting amount is very small or negligible, it may not cause any harmful effect on baby s overall developmental progress and growth. Cerazette is a mini pill, as it contains progesterone only, so it is a safer option for the breastfeeding mother according to the various evidence based studies, gynecologist s advice etc. Without any investigations and further evaluations, it is difficult to predict the exact causes of bleeding and when or how your present bleeding will be stopped. So, you should consult your doctor for further investigations and evaluations as well as ask your doctor if you have any queries. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Zubayer Alam, General And Family Physician