Hello Doctor, I had taken Sysron N the first month for 4 days 1 tablet each day to delay my periods and in two days got my periods on stopping the tablet.yet again in the second month took the tablet for 5 days, and on stopping got my periods back in 2 days. Third month i didn t take the tablet but my periods got delayed by 15 days starting with spotting on the first two days, then it went as regular. But now the problem is it is there for more than a week. No chance of pregnancy either, had done the test which came out negative. I want to know why the periods got delayed and it is prolonged this time?