HELLO, i can understand your concern. metformin is used in pcos for the treatment of insulin resistance which is seen in the syndrome. metformin has an added benefit of reducing weight which plays an important role in pcos management. i would like to know if you have been using hormonal pills and drugs like clomiphene which are used along with metformin. delay in a single cycle is not much of a concern.. i would like to know if there is any chance of you getting pregnant. since you have been using medications for pcos there is good chance of getting pregnant. in case there is no chance of pregnancy i would suggest wait for a few days and if the periods do not start ,you will be required to take a course of hormones. a hormonal study and an ultrasound is also advised. i would suggest continuation of metformin as it has a key role in the management of pcos. hope you are satisfied with our response. do revert back for further queries. thanks for choosing HCM