The dawn phenomenon, also known as the dawn effect, is a term used to describe an abnormal rise in blood sugar that occurs in the early hours of the morning in people with diabetes – usually between 2 a.m. and 8 a.m. Some scholars believe that in the natural state everyone releases and secretes hormones during the night (the latter half of the night) – such as growth hormone, cortisol, glucagon and adrenaline – and that in people with diabetes, the secretion of these hormones may lead to an increase in insulin resistance, which in turn raises blood glucose. In addition, early morning hyperglycemia can be caused by: insufficient insulin injections the night before; improper medication dosing at dinner or before bedtime; or consuming too many carbohydrate-containing snacks or sweets before going to bed. If you have recently had persistent early morning fasting hyperglycemia, it is recommended that you monitor your finger glucose at night (usually between 2:00 a.m. and 3:00 a.m.) for 3 to 5 days in a row and record the monitoring time and glucose value on a sheet. This will help you or your doctor to identify the cause to determine if you have recently had a dawn phenomenon or if there is some other reason for your early morning hyperglycemia. Of course, your doctor may give you some advice to help prevent or correct your early morning hyperglycemia.