IRCT2014010116025N1 IRCT 2014-05-18 Vice Chancellor for Research and Technology, Hormozgan University of Medical Sciences Metformin is more effective than insulin in treating gestational diabetes Comparing of the effectiveness of insulin and metformin in treating gestational diabetes 2014-01-28 anticipated 400 Complete https://irct.ir/trial/15109 interventional Randomization: Randomized, Blinding: Single blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment. 2-3 gestational diabetes. Intervention 1: In the metformin group, the treatment will begin with 500 mg of metformin (produced by Apotex company, holding the trademark; Apo Metfromin). It will be given once or twice a day starting with meals so that within a 1 to 2 week’s time the target blood glucose is reached or to the maximum level of 2500 mg of daily dosage it will be increased. In case the treatment target is not reached through the mere consumption of metformin, three weeks (on average) after the beginning of metformin treatment, insulin will be added. If taking metformin is inhibited for the mother (if she suffers from some sort of liver, kidney disorder or sepsis) or detect intra uterin growth retardation stop the use of metformin. Intervention 2: Insulin will be used in a 0.5 to 1 unit/kg dosage dependent on the pregnancy age (in the 1st trimester: 0.5 unit/kg, 2nd trimester: 0.7 unit/kg and the 3rd trimester: 1 unit/kg). According to the Multi day injection rule, we will start with NPH and regular insulin.