hi.if ur preg test is neg. that means its ur polycystic ov that is delaying ur periods. metformin
[glucophage] is a good treatment option for polycysts but the tolerence of this medicine is generally poor.hence it shud b started with a v low dose.. i.e as low as 250mg/day[ 500 mg tab half daily]. n go on increasing d dose every 7-10 days by 25 mgs. apart from this life stye
modification help too i.e. regular excercise, yoga
n fat free diet. so gud luck n happy exercising.