It is not unusual for the hairline to mature and lose the frontal 3/4 inch upward. I call this a maturing hairline but it is not always uniform and it can start in the center anytime between the ages of 18-29 years. This can also be a sign of genetic balding but your hairline looks flat and low. You should see a doctor to determine just where this is coming from. The doctor will perform both a HAIRCHECK test of your entire scalp and miniaturization studies of your frontal hairline.