What Are The Advantages And Disadvantages Of Using Susten 100mg?

i have irregular periods before marraige after marraige i was suggested to susten 100 mg daily 2 , when i started this i got periods 5 days after completion of medicine , since from 2 months i am getting 2 days after completion , this month i got on the last day of the usage itself , is this a dange , y actually susten used , and what are the advantages and disadvantages of using susten