Hi, I'm 32 years old and suffering from absent periods past few years. doctor has prescribed me metformin 500mg daily twice and duphaston 10mg from 5th day of the cycle to 21st day. I want to conceive as well. I've observed that if I stop duphaston anytime between 5th- 21st day, due to shortage of pill or if i get delayed in taking it. I get period within two days. why does it happen? Is my system very critical of with hormonal imbalance? doctors say its cyst in ovaries. please guide.