Hi, I normally take norethisterone 5mg one three times a day for 2 weeks then my period comes on the 4th day of stopping them, I do this every 2/3 months as I have pcos and don t have any menstrual cycle. I am now currently receiving ivf treatment, today I was prescribed provera to take one three times a day for 7 days and a period should come on the 3rd or 4th day of stopping then I have to phone them to begin my treatment, will this work? are the two drugs the same? and is 7 days long enough for a period to come?