Can PCOS Cause Delayed Periods?

Hi, I am 26 yr old. Got married 5 months ago. after which i had irregular periods. i checked and i had PCOS. the doctor has suggested me to have g-reg sr 500 & krimson 35 for 3 months. for the 3 months i was getting my periods, even the 4th month i got my periods on 25th day. this month i still have not got. now its 30th day. as it is just 30th day, i dint go to the hospital. pls suggest me and explain what is happening.