What is the cause for scanty periods?

Q: During periods, my wife was complaining that the bleeding was there only for 2 days and it was very less. Why does this happen? The doctor told us to get a sonography done. Why is it done?

A:A scanty period may be a result of several possibilities including a normal variation, a hormonal imbalance, stress or a pregnancy in the tube. A sonography will throw light on many of these and is therefore indicated.