Background Factors Determining the Introduction and Dosage of Insulin in Women With Gestational Diabetes Mellitus

BACKGROUND: Gestational diabetes mellitus (GDM) is a risk for perinatal complication, and appropriate diagnosis of and intervention in this condition are important. This study aimed to identify patient factors associated with introduction and dosage of insulin, which is the main drug for treatment of GDM. METHODS: In total, 114 patients who had been diagnosed with GDM at our hospital were included in this study. We retrospectively collected clinical parameters of GDM patients, including how many times positive glucose tolerance test results were obtained, whether insulin was introduced, dosage of insulin, body weight, and infant weight. Background factors differing between the insulin introduction and non-introduction groups of GDM patients and parameters associated with the insulin dosage were analyzed. RESULTS: Insulin was introduced in 51 GDM patients (45%). In the insulin introduction group, the six-divided diet was less common and the 75-g glucose tolerance test result was positive a significantly greater number of times compared with the non-introduction group. The factor associated with the insulin introduction status was the number of positive 75-g glucose tolerance test results (odds ratio (OR) 2.04, 95% confidence interval (CI): 1.09 - 3.81, P value = 0.025). In addition, the insulin dosage was found to positively correlate with body weight in the non-pregnant state (P value = 0.005). CONCLUSIONS: The six-divided diet was effective for blood glucose control in GDM women. A positive correlation found between the insulin dosage and body weight in the non-pregnant state suggests the importance of proper pre-pregnancy body weight control.