Hi, for about one year now my period starts in its regular time but as brown discharge for5 to 6 days then as normal flow for another 5 days this month I was under fertility treatment and my period was late one day from due date and the next day I see brown discharge very slight only when I wipe so any possibility to be pregnant please help

No sounds like chocolate cysts! As your doctor about this. Large cysts develop, particularly with fertility treatment... and the blood just stays in the cyst a little long before the egg breaks free to do it's thing.

But if you are trying to get pregnant, it's worthwhile to note that there can be some small spotting when conception takes place. But you don't need me to tell you to do a pregnancy test, do you!? Go do it and let us know what you find out!. and make an appointment with your doctor either way!